isl_map_simple_hull: plug memory leak
isl_map_simple_hull: plug memory leak

The leak was introduced in 4433b45d31f7f5461ee372a8a4aa2d3a955f96b5
(isl_map_underlying_set: align divs before calling this function).

Meinersbur/isl,Distrotech/isl,cfx-next/toolchain_isl-upstream,jleben/isl,SaberMod/isl-current,KangDroidSMProject/ISL,Distrotech/isl,inducer/isl-mirror,jleben/isl,epowers/isl,epowers/isl,serge-sans-paille/isl,SaberMod/isl-current,jleben/isl,evaautomation/isl,simbuerg/isl,tobig/isl,pierrotdelalune/isl,BobSaget-Mod/libisl,simbuerg/isl,KangDroidSMProject/ISL,cfx-next/toolchain_isl-upstream,VanirLLVM/toolchain_isl,Meinersbur/isl,crossbuild/isl,Meinersbur/isl,pierrotdelalune/isl,nicolasvasilache/isl,jleben/isl,nicolasvasilache/isl,abduld/isl,BenzoSM/isl,simbuerg/isl,cfx-next/toolchain_isl-upstream,VanirLLVM/toolchain_isl,abduld/isl,UBERTC/isl,KangDroidSMProject/ISL,PollyLabs/isl,BenzoSM/isl,epowers/isl,UBERTC/isl,SaberMod/isl-current,VanirLLVM/toolchain_isl,Meinersbur/isl,serge-sans-paille/isl,serge-sans-paille/isl,jleben/isl,VanirLLVM/toolchain_isl,evaautomation/isl,simbuerg/isl,cfx-next/toolchain_isl-upstream,UBERTC/isl,Distrotech/isl,BobSaget-Mod/libisl,PollyLabs/isl,evaautomation/isl,cfx-next/toolchain_isl-upstream,tobig/isl,PollyLabs/isl,serge-sans-paille/isl,abduld/isl,VanirLLVM/toolchain_isl,KangDroidSMProject/ISL,tobig/isl,BenzoSM/isl,BenzoSM/isl,tobig/isl,Distrotech/isl,SaberMod/isl-current,KangDroidSMProject/ISL,inducer/isl-mirror,crossbuild/isl,BenzoSM/isl,BobSaget-Mod/libisl,simbuerg/isl,crossbuild/isl,PollyLabs/isl,UBERTC/isl,pierrotdelalune/isl,BobSaget-Mod/libisl,PollyLabs/isl,pierrotdelalune/isl,BobSaget-Mod/libisl,Distrotech/isl,inducer/isl-mirror,serge-sans-paille/isl,nicolasvasilache/isl,inducer/isl-mirror,crossbuild/isl,abduld/isl,nicolasvasilache/isl,epowers/isl,evaautomation/isl,epowers/isl,nicolasvasilache/isl,inducer/isl-mirror,pierrotdelalune/isl