SpirvShaderDebugger: Add flag for printing opcodes
SpirvShaderDebugger: Add flag for printing opcodes

The `PRINT_EACH_PROCESSED_INSTRUCTION` preprocessor flag can control printing of each instruction before they are processed.
This is exceptionally helpful when debugging the debugger (or anything else to do with SpirvShader).

Bug: b/145351270
Change-Id: Iddfbedbfc86487d71f6980b2f3fb74f7f13e972f
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/40093
Reviewed-by: Nicolas Capens <51edc787c30f24c4904e8ffbb5523c3a9f7a451d@google.com>
Tested-by: Ben Clayton <1f693eb7158dc33015048c09d6712f74dabddf79@google.com>
Kokoro-Presubmit: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>

google/swiftshader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,google/swiftshader,google/swiftshader,bkaradzic/SwiftShader,bkaradzic/SwiftShader