Hi,

This enables and makes it more likely the compiler is able to use GPR 
input for SIMD inserts. I believe this is some outdated hack we used to 
prevent costly GPR<->SIMD register file swaps. This patch is required 
for better codegen in situations like the test case 'int8_3' in the next 
patch in this series.

Bootstrapped and regression tested together with the next patch on 
aarch64-none-linux-gnu.

gcc/ChangeLog:

2022-08-05  Andre Vieira  <andre.simoesdiasvieira@arm.com>

         * config/aarch64/aarch64-simd.md (aarch64_simd_vec_set<mode>): 
Remove '?' modifier.