msm: socinfo: Refactor machine_is macros

Replace SoC-specific machine_is macros with SoC-independent
equivalents wherever the SoC type is already defined by the
context of the call site. Generalize some of the platsmp
machine_is logic in the process to facilitate future
support for simulation platforms.

Change-Id: I9e164b8f9515054dd634518b26b98d4849bd9b82
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>