btm: allow BTM_VSC_CHIP_CAPABILITY_RSP_LEN_M_RELEASE to be adjustable

Some BCM firmwares shipped with LGE devices will not pass a check involving the BTM_VSC_CHIP_CAPABILITY_RSP_LEN_M_RELEASE capability.

This commit allows BTM_VSC_CHIP_CAPABILITY_RSP_LEN_M_RELEASE to be adjusted as a workaround for these firmwares.
This issue was seen on some v20 and g5 oreo release BCM firmwares and the BCM4358A3_001.004.015.0095.0168_KR_ORC.HCD fw found
on the v20 f800k pie release (lge/elsa_kt_kr/elsa:9/PKQ1.190522.001/20192161159c5)

Log snippet:
```
08-14 11:16:52.534  3468  3468 F DEBUG   : Abort message: '[FATAL:btm_ble_gap.cc(668)] Check failed: p_vcs_cplt_params->param_len >= BTM_VSC_CHIP_CAPABILITY_RSP_LEN_M_RELEASE.
```

Change-Id: I1fccfd0f8877bdc878e7a2068f654369b136956e