arm: common: Add indirect L2 rw support for cpaccess

Added indirect L2 rw support to cpaccess kernel module. Input format
change to include a parameter to specify register access type. Validation
if register type is one of supported types.

Change-Id: I5bd52c89d87a4fb4da4248526e56079bb604f910
Signed-off-by: Suren Eda Naarayana Kulothungan <sedanaar@codeaurora.org>
(cherry picked from commit 4c317fbf87a93d8e34e33063b6164e5d5c32cdd0)