aco: When LS and HS invocations are the same, pass LS outputs in temps.

aco: When LS and HS invocations are the same, pass LS outputs in temps.

We know that in this case, the LS and HS invocations are working
on the exact same vertex, so it's safe to skip the LDS.

Totals:
VGPRS: 3960744 -> 3961844 (0.03 %)
Code Size: 254824300 -> 254764624 (-0.02 %) bytes
Max Waves: 1053748 -> 1053574 (-0.02 %)

Totals from affected shaders:
VGPRS: 26152 -> 27252 (4.21 %)
Code Size: 1496600 -> 1436924 (-3.99 %) bytes
Max Waves: 4860 -> 4686 (-3.58 %)

Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4165>