p9.11 and p9.13 not available in BB Industrial - RJ485

Hi, following your instructions to use RJ485 communication (for modbus) I'm getting the following error when trying to configure UART4

```bash
(penv39) debian@beaglebone:/opt/source/beagle-tester$ config-pin p9.11 uart
ERROR: open() for /sys/devices/platform/ocp/ocp:P9_11_pinmux/state failed, No such file or directory
(penv39) debian@beaglebone:/opt/source/beagle-tester$ config-pin p9.13 uart
ERROR: open() for /sys/devices/platform/ocp/ocp:P9_13_pinmux/state failed, No such file or directory
```
I'm using kernel `Linux beaglebone 4.19.94-ti-r74 #1buster SMP PREEMPT Tue Jun 27 20:53:24 UTC 2023 armv7l GNU/Linux` and this is my `/boot/uEnv.txt` file

```bash
#Docs: http://elinux.org/Beagleboard:U-boot_partitioning_layout_2.0

uname_r=4.19.94-ti-r74
#uuid=
#dtb=

###U-Boot Overlays###
###Documentation: http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#U-Boot_Overlays
###Master Enable
enable_uboot_overlays=1
###
###Overide capes with eeprom
#uboot_overlay_addr0=/lib/firmware/.dtbo
#uboot_overlay_addr1=/lib/firmware/.dtbo
#uboot_overlay_addr2=/lib/firmware/.dtbo
#uboot_overlay_addr3=/lib/firmware/.dtbo
###
###Additional custom capes
#uboot_overlay_addr4=/lib/firmware/.dtbo
#uboot_overlay_addr4=/lib/firmware/BB-UART4-RS485-00A0.dtbo
#uboot_overlay_addr5=/lib/firmware/.dtbo
#uboot_overlay_addr6=/lib/firmware/.dtbo
#uboot_overlay_addr7=/lib/firmware/.dtbo
###
###Custom Cape
#dtb_overlay=/lib/firmware/.dtbo
###
###Disable auto loading of virtual capes (emmc/video/wireless/adc)
#disable_uboot_overlay_emmc=1
disable_uboot_overlay_video=1
disable_uboot_overlay_audio=1
disable_uboot_overlay_wireless=1
disable_uboot_overlay_adc=1
###
###PRUSS OPTIONS
###pru_rproc (4.14.x-ti kernel)
#uboot_overlay_pru=/lib/firmware/AM335X-PRU-RPROC-4-14-TI-00A0.dtbo
###pru_rproc (4.19.x-ti kernel)
uboot_overlay_pru=/lib/firmware/AM335X-PRU-RPROC-4-19-TI-00A0.dtbo
###pru_uio (4.14.x-ti, 4.19.x-ti & mainline/bone kernel)
#uboot_overlay_pru=/lib/firmware/AM335X-PRU-UIO-00A0.dtbo
###
###Cape Universal Enable
enable_uboot_cape_universal=0
###
###Debug: disable uboot autoload of Cape
#disable_uboot_overlay_addr0=1
#disable_uboot_overlay_addr1=1
#disable_uboot_overlay_addr2=1
#disable_uboot_overlay_addr3=1
###
###U-Boot fdt tweaks... (60000 = 384KB)
#uboot_fdt_buffer=0x60000
###U-Boot Overlays###

cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet

#In the event of edid real failures, uncomment this next line:
#cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet video=HDMI-A-1:1024x768@60e

##enable Generic eMMC Flasher:
##make sure, these tools are installed: dosfstools rsync
#cmdline=init=/opt/scripts/tools/eMMC/init-eMMC-flasher-v3.sh
```

I also tried using overlay pointing to `/lib/firmware/BB-UART4-00A0.dtbo|BB-UART4-RS485-00A0.dtbo`, but still can't see the pins there.
The `config-pin` run ok in beagle bone **black**, but no on my industrial board. Is there something missing to enable UART4?

Start with the reported config-pin failures for p9.11 and p9.13 and inspect /boot/uEnv.txt, including the commented BB-UART4-00A0.dtbo and BB-UART4-RS485-00A0.dtbo overlay entries. Compare the Industrial and Black board setup under the reported 4.19.94-ti-r74 kernel; done means UART4 can be configured and both pins are available.

Written by the indexing model from the issue text.