arm64/sysreg: Allow leading blanks on comments in sysreg file

Currently we only accept comments where the # is placed at the start of a
line, allow leading blanks so we can format comments inside definitions in
a more pleasing manner.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-4-broonie@kernel.org


Signed-off-by: Will Deacon <will@kernel.org>