soc: qcom: spcom: Add changes for loading SP in UEFI

Upon power up Secure Processor is brought up in the UEFI stage.
A change is made to the APPS SPCOM kernel code to overwrite a
function pointer used inside the APPS Peripheral Image Loader
power up API that would cause Peripheral Image Loader to not
trigger start of Secure Processor subsystem.
Upon Secure Processor subsystem restart however, the regular
Peripheral Image Loader power up API is invoked as usual in
order to trigger restart of Secure Processor subsystem. In
this case a change is made to SPCOM kernel to set a register
to indicate to Secure Processor that the reset is due to
subsystem event so that it can synchronize accordingly with
Peripheral Image Loader.

Change-Id: I11101f608f4acf461c9f9d5f3ee1618ffc917066
Signed-off-by: Amandeep Virk <avirk@codeaurora.org>