ArmPlatformPkg/PL180MciDxe: fix Depex for TC2

ArmPlatformPkg/PL180MciDxe: fix Depex for TC2

PL180 on TC2 has a dependency on gEfiCpuArchProtocolGuid.  Without
adding the dependency, TC2 will crash in the PL180 driver.

This problem has been present since d340ef7 when TC2 stopped booting.
However, it was masked by 300fc77 which prevented PL180 from running on
TC2 due to TC2 using a version on PL180 newer than that documented
publicly.

[1] https://github.com/tianocore/edk2/commit/d340ef7
2014-08-26
ArmPkg/ArmArchTimerLib: Remove non required [depex] and IoLib
[2] https://github.com/tianocore/edk2/commit/300fc77
2015-08-25
ArmPlatformPkg/PL180MciDxe: check PrimeCell ID before initializing

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>