bug: use of deprecated interface triggers a warning/stack trace in the kernel log for RaspberryPi devices

### Bug description

When looking at `dmesg` on RaspberryPi devices running BlueOS, the following warning shows up, followed by a stack trace:

```
[ 105.119232] ------------[ cut here ]------------
[ 105.119280] WARNING: CPU: 0 PID: 1918 at drivers/firmware/raspberrypi.c:234 get_throttled_show+0x6c/0x70
[ 105.119293] deprecated, use hwmon sysfs instead
[ 105.119303] Modules linked in: tcp_diag inet_diag nf_conntrack_netlink xt_nat xt_tcpudp xt_conntrack xt_MASQUERADE bridge xt_set ip_set nft_counter nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_addrtype nft_compat nf_tables nfnetlink cmac algif_hash aes_arm_bs crypto_simd cryptd algif_skcipher af_alg bnep hci_uart btbcm bluetooth ecdh_generic ecc overlay 8021q garp stp llc brcmfmac brcmutil sha256_generic cfg80211 snd_bcm2835(C) rfkill snd_pcm raspberrypi_hwmon snd_timer snd bcm2835_codec(C) bcm2835_isp(C) v4l2_mem2mem videobuf2_dma_contig uio_pdrv_genirq uio fixed i2c_dev i2c_bcm2835 bcm2835_v4l2(C) bcm2835_mmal_vchiq(C) vc_sm_cma(C) videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common videodev mc fuse drm drm_panel_orientation_quirks backlight ip_tables x_tables ipv6
[ 105.120058] CPU: 0 PID: 1918 Comm: linux2rest Tainted: G C 5.10.33-v7+ #1415
[ 105.120065] Hardware name: BCM2835
[ 105.120072] Backtrace:
[ 105.120097] [<809eda64>] (dump_backtrace) from [<809eddf4>] (show_stack+0x20/0x24)
[ 105.120110] r7:ffffffff r6:00000000 r5:600a0013 r4:80ee5e14
[ 105.120127] [<809eddd4>] (show_stack) from [<809f1fa0>] (dump_stack+0xcc/0xf8)
[ 105.120144] [<809f1ed4>] (dump_stack) from [<8011ed1c>] (__warn+0xfc/0x114)
[ 105.120159] r10:9fb59ef8 r9:00000009 r8:8082a498 r7:000000ea r6:00000009 r5:8082a498
[ 105.120168] r4:80c6c918 r3:80e05050
[ 105.120182] [<8011ec20>] (__warn) from [<809ee474>] (warn_slowpath_fmt+0xa4/0xd8)
[ 105.120194] r7:000000ea r6:80c6c918 r5:80e05008 r4:80c6c9b0
[ 105.120211] [<809ee3d4>] (warn_slowpath_fmt) from [<8082a498>] (get_throttled_show+0x6c/0x70)
[ 105.120226] r9:9fa5f900 r8:815c8010 r7:83d4a000 r6:80a48aa4 r5:815cc4c0 r4:83d4a000
[ 105.120245] [<8082a42c>] (get_throttled_show) from [<80708abc>] (dev_attr_show+0x28/0x54)
[ 105.120256] r5:80f14c48 r4:859611e0
[ 105.120275] [<80708a94>] (dev_attr_show) from [<803ea29c>] (sysfs_kf_seq_show+0x98/0x100)
[ 105.120286] r5:00001000 r4:859611e0
[ 105.120300] [<803ea204>] (sysfs_kf_seq_show) from [<803e8314>] (kernfs_seq_show+0x34/0x38)
[ 105.120315] r9:859611f8 r8:00000000 r7:00000001 r6:00400cc0 r5:00001000 r4:859611e0
[ 105.120330] [<803e82e0>] (kernfs_seq_show) from [<8035f56c>] (seq_read_iter+0x188/0x4d4)
[ 105.120344] [<8035f3e4>] (seq_read_iter) from [<803e8990>] (kernfs_fop_read_iter+0x140/0x188)
[ 105.120360] r10:9fb59ee0 r9:00000000 r8:00000000 r7:9fb59ef8 r6:00001000 r5:943da840
[ 105.120367] r4:9fa5f900
[ 105.120383] [<803e8850>] (kernfs_fop_read_iter) from [<8033286c>] (vfs_read+0x218/0x344)
[ 105.120398] r10:9fb59f58 r9:00000000 r8:00000000 r7:80e05008 r6:00001000 r5:943da840
[ 105.120405] r4:00000000
[ 105.120421] [<80332654>] (vfs_read) from [<80332e64>] (ksys_read+0x68/0xe0)
[ 105.120436] r10:00001000 r9:76a19da0 r8:943da840 r7:00000000 r6:00000000 r5:943da843
[ 105.120443] r4:80e05008
[ 105.120461] [<80332dfc>] (ksys_read) from [<80332ef4>] (sys_read+0x18/0x1c)
[ 105.120475] r10:00000003 r9:9fb58000 r8:80100204 r7:00000003 r6:000000a9 r5:76a19da0
[ 105.120483] r4:00001000
[ 105.120499] [<80332edc>] (sys_read) from [<80100040>] (ret_fast_syscall+0x0/0x28)
[ 105.120508] Exception stack(0x9fb59fa8 to 0x9fb59ff0)
[ 105.120521] 9fa0: 00001000 76a19da0 000000a9 76a19da0 00001000 00000000
[ 105.120537] 9fc0: 00001000 76a19da0 000000a9 00000003 00001000 76a19da0 00000000 76d495a0
[ 105.120548] 9fe0: 00000003 76d49538 76df23a1 76d6b656
[ 105.120557] ---[ end trace 62359b3bf493d5c5 ]---
```

### Steps to reproduce

1. Flash and boot BlueOS on a RaspberryPi device (I've been using a RPI 3B v1.2)
2. Inspect the output of `dmesg` and grep for `get_throttled_show`

### Primary pain point(s)

This is a common red herring that raises some eyebrows when inspecting the system logs during debugging of unrelated issues.

### Additional context

_No response_

### Prerequisites

- [x] I have checked to make sure that a similar request has not already been filed or fixed.