tuna: PowerHAL: Change obsolete designated initializers syntax

Designated initializers syntax which is used to initialize
HAL_MODULE_INFO_SYM is obsolete since GCC 2.5:
http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html

This patch changes syntax to usual one.

Cherry-picked from http://omapzoom.org/?p=device/ti/blaze_tablet.git;a=commit;h=361e9eab2dd455588327612c31623396725fdb1a

Change-Id: I7ed930bd6cf0f44f1503947c9abbc93a9ef99821
tuna: PowerHAL: Check that PowerHAL is successfully initialized

It doesn't make any sense to do something if PowerHAL
couldn't setup initial parameters successfully.

Cherry-picked and adjusted for tuna from
http://omapzoom.org/?p=device/ti/blaze_tablet.git;a=commit;h=5b250f0dbc8fa43f8ff9e45151730b5b733c5ed0

Change-Id: I4e87f6b7be53e52f21f02cc500c8a1096f70df5f
tuna: PowerHAL: Define constants for CPUfreq paths

Same CPUfreq paths are used many times in the code.
This patch defines constants for them.

Cherry-picked and adjusted for tuna from
http://omapzoom.org/?p=device/ti/blaze_tablet.git;a=commit;h=f5ee7ba155978bd9e547c079b521a1a249bdefab

Change-Id: I07519ad70a2f243c6fe68b26dc8b409e6223772e