feat(spmd): initialize SCR_EL3.EEL2 bit at RESET

SCR_EL3.EEL2 bit enabled denotes that the system has S-EL2 present and
enabled, Ideally this bit is constant throughout the lifetime and
should not be modified. Currently this bit is initialized in the context
mgmt code where each world copy of the SCR_EL3 register has this bit set
to 1, but for the time duration between the RESET and the first exit to
a lower EL this bit is zero.

Modifying SCR_EL3.EEL2 along with EA bit at RESET does also helps in
mitigating against ERRATA_V2_3099206.

For details on Neoverse V2 errata 3099206, refer the SDEN document
given below.
https://developer.arm.com/documentation/SDEN-2332927/latest

Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: If8b2bdbb19bc65391a33dd34cc9824a0203ae4b1
1 file changed