GICv3: turn some macros into inline functions
GICv3: turn some macros into inline functions

Tidy up the code a bit by turning some macros into inline functions
which allows to remove the do/while(0) idiom and backslashes at the end
of the line.

Change-Id: Ie41a4ea4a4da507f7b925247b53e85019101d717
Signed-off-by: Douglas Raillard <689105a89352b3b1d4ffa5bfffd804efe641e037@arm.com>

lsigithub/arm-trusted-firmware_public,achingupta/arm-trusted-firmware,achingupta/arm-trusted-firmware,lsigithub/arm-trusted-firmware_public