Both im2col.comp and im2col_3d.comp declare D_ptr without an explicit
buffer_reference_align, so glslang emits writes through it as Aligned
16. The shaders advance the pointer by D_SIZE, a per-variant define
set to 4 for float and 2 for float16_t, so most write addresses are
not 16-byte aligned. This triggers
VUID-RuntimeSpirv-PhysicalStorageBuffer64-06315 under GPU-AV.
Declaring buffer_reference_align = D_SIZE matches the alignment to the
actual write stride and takes validation hits from 20 to 0 for both
IM2COL and IM2COL_3D.
Fixes#28960
