msm_shared: Write LK log to RAM buffer

LK log messages are written to static RAM buffer.
The size of the buffer can be set with compile time define.

The LK log starts with a cookie (4bytes), max log size (4b) and
actual log size written (4b). If size written is greater than max
size then overlap has occured and latest prints have overwritten
the first ones (circular write).

Writting LK log is enabled per target with compile time define.

Change-Id: I52d3e06d0b286578d18a32969455501e2a275833
1 file changed