rename basic_map_partial_lexopt*_map to basic_map_partial_lexopt*
rename basic_map_partial_lexopt*_map to basic_map_partial_lexopt*

This ensures that the "map" versions of the partial_lexopt
functions have the same suffix, i.e., an empty suffix.
This will be useful for merging the "map" and the "pw_multi_aff"
versions into a single implementation.

Signed-off-by: Sven Verdoolaege <e5350bbed4977f5eb8ae1dc6abd9ae59d21ace75@kotnet.org>

UBERTC/isl,PollyLabs/isl,nicolasvasilache/isl,tobig/isl,inducer/isl-mirror,PollyLabs/isl,PollyLabs/isl,nicolasvasilache/isl,nicolasvasilache/isl,PollyLabs/isl,tobig/isl,tobig/isl,UBERTC/isl,nicolasvasilache/isl,nicolasvasilache/isl,PollyLabs/isl,UBERTC/isl,Meinersbur/isl,inducer/isl-mirror,Meinersbur/isl,UBERTC/isl,Meinersbur/isl,inducer/isl-mirror,tobig/isl,Meinersbur/isl,inducer/isl-mirror,inducer/isl-mirror