misleading test names in test_spirv_new for no integer wrap decoration

[bashbaug]

See review comment: https://github.com/KhronosGroup/OpenCL-CTS/pull/2041#discussion_r1724790832

The test names and SPIR-V asm filenames for the "no integer wrap decoration" tests are "fadd", "fsub", etc., which implies that they're testing floating-point operations, but they're actually testing integer operations. We should fix this by renaming the test names and the SPIR-V asm files.