refactor(cm): move mpam registers into el2 context

* FEAT_MPAM related EL2 registers are placed explicitly outside
  the EL2 context in the cpu_context_t structure.

* With EL2 registers now coupled with dependent features, this
  patch moves them to the el2_context structure "el2_sysregs_t".

* Further, converting the assembly context-offset entries into a
  c structure. It relies on garbage collection of the linker
  removing unreferenced structures from memory, as well as aiding
  in readability and future maintenance.

Change-Id: Ib784bc8d2fbe35a8a47a569426d8663282ec06aa
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
3 files changed