backend/x86: Use objdump to dump emitted bytecode.
Teardown SDL support in the test application (for cross-platform demo).

Also use proper timeops operations.
Do not search for uXray (does not work in win32).
Add mingw32 cmake toolchain file.
Add some debug-verbosity in reading bytecode files (dump section magics as strings).
Update uXray (branch switch and cross-platform fixes).