SMS_Ly1_Mmpi-serial.1x1_brazil.IHistClm50BgcQianRs.cheyenne_gnu.clm-output_bgc_highfreq fails with MIMICS

### Brief summary of bug

With MIMICS active, _SMS_Ly1_Mmpi-serial.1x1_brazil.IHistClm50BgcQianRs.cheyenne_gnu.clm-output_bgc_highfreq_ fails with error:
`MET_LITC_TO_ACT_SOMC in fincl(22) for history tape 1 not found`

### General bug information

**CTSM version you are using:** ctsm5.1.dev073-79-geba8244

**Configurations affected:** soil_decomp_method = 'MIMICSWieder2015'

### Details of bug

In _cime_config/usermods_dirs/output_bgc_ I found the user_nl_clm that sets:
`hist_fincl1 += 'MET_LITC_TO_ACT_SOMC'`
Other fields listed in the same hist_fincl1 will likely also not be found when running MIMICS. This is expected because the decomp. transitions represented in MIMICS differ from the ones represented in CENTURY. The simplest solution is to remove all fields that trigger the error.

I am open to other suggestions.