msm: smcmod: Added ioctl to decrypt PIL segment images

The new proposed ioctl will be used to decrypt images during
Google OTA update from recovery mode. It makes a request to
secure world and receives a response with status. The
decryption is executed by secure world code.

Change-Id: I667ec5f7918f271f82c1942c21f09bf3e932e874
Signed-off-by: Stanimir Varbanov <svarba@codeaurora.org>