glsl: Handle packed_type == ivec4[] in lower_packed_varyings().
glsl: Handle packed_type == ivec4[] in lower_packed_varyings().

For GS input arrays, we may turn a packed_type of ivec4 into an
array of ivec4s.  We still want flat qualification.

Found by inspection.  Not known to help anything.

Signed-off-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>
Reviewed-by: Iago Toral Quiroga <a847aabaac44184372f6b1cd1a59aa254daaeb0b@igalia.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler