r600/shader: handle fetching tcs/tes inputs and tcs outputs
r600/shader: handle fetching tcs/tes inputs and tcs outputs

This handles the logic for doing fetches from LDS for
TCS and TES. For TCS we need to fetch both inputs and outputs,
for TES only inputs need to be fetched.

v2: use 24-bit ops.

Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler