feat(msm8916): expose more timer frames

feat(msm8916): expose more timer frames

The memory-mapped generic timer on msm8916 has 7 timer frames, but
currently only one is exposed for usage in the non-secure world.

The platform port is currently only designed to be used as minimal PSCI
implementation, without secure world that could make use of the other
timer frames. Let's make all of them available to the normal world.

If needed this could still be changed later by reserving some timer
frames conditionally to a specific SPD being enabled in the build.

Change-Id: Ib59df16aa1fd3dbc875ab6369c133737830c98c6
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>