We need to push loop nesting to handle this correctly -- at the end of
the innermost loop, the correct nesting is 1 (from the if), not 0.
Fixes assertion failure in
dEQP-GLES2.functional.shaders.struct.local.dynamic_loop_nested_struct_array_fragment,UnexpectedPass
dEQP-GLES2.functional.shaders.struct.local.dynamic_loop_nested_struct_array_vertex,UnexpectedPass
dEQP-GLES2.functional.shaders.struct.uniform.dynamic_loop_nested_struct_array_fragment,UnexpectedPass
dEQP-GLES2.functional.shaders.struct.uniform.dynamic_loop_nested_struct_array_vertex,UnexpectedPass
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17128>