glsl: Fixes for mixed 32/64 bit integers on both sides of shift operator
This MR fixes:
- 64-bit integers on the RHS of the shift operators
- codegen of constant ir_binop_{l,r}shift caring only about the type of the LHS source, and thus computing wrong data when the LHS and RHS types are mismatched.
Signed-off-by: Sviatoslav Peleshko sviatoslav.peleshko@globallogic.com