msm: physical offset for QSD8x50

Support different RAM base addresses used by Qualcomm SOCs, with
QSD8x50 as the first addtional one.

Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Gregory Bean <gbean@codeaurora.org>
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>