msm: kgsl: Make use of ADRENO_CONTENT_PROTECTION flag

A5x GPU comes up in secure mode by default but sometimes it
doesn't support content protection and corresponding
secure microcode. GPU cannot be moved to unsecure
mode without secure microcode.

Insert PM4 commands to move the GPU from secure to
unsecure only if it has ADRENO_CONTENT_PROTECTION feature
otherwise fallback to CPU and reset the register
A5XX_RBBM_SECVID_TRUST_CNTL.

Change-Id: I8c4ac26f3ef2b87a46bb2d171d2be6af75425d67
Signed-off-by: Rajesh Kemisetti <rajeshk@codeaurora.org>
Signed-off-by: Hareesh Gundu <hareeshg@codeaurora.org>