android: panfrost: Move nir_undef_to_zero to util

clang: error: no such file or directory: 'external/mesa3d/src/panfrost/midgard/nir_undef_to_zero.c'
clang: error: no input files

Fixes: 86b2b4eb ("panfrost: Move nir_undef_to_zero to common util/")

!7206 (merged)