[01/11] kernel32/tests: Consolidate duplicated code for invalid LCMapString flag tests.

[Marvin]

Hi,

While running your changed tests on Windows, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?
Full results can be found at
https://testbot.winehq.org/JobDetails.pl?Key=25903

Your paranoid android.


=== w1064 (32 bit locale) ===
locale.c:2535: Test failed: LCMapStringEx should fail with bad locale name
locale.c:2536: Test failed: unexpected error code -559038737
locale.c:2627: Test failed: Expected lcid == 0, got 00001000, error -559038737
locale.c:4363: Test failed: IsValidLocaleName should have failed
locale.c:4365: Test failed: IsValidLocaleName should have failed
locale.c:4748: Test failed: For id 7, expected ret == 4, got 1, error 87
locale.c:4750: Test failed: For id 7, Expected IVC, got ''

=== w1064 (64 bit locale) ===
locale.c:2535: Test failed: LCMapStringEx should fail with bad locale name
locale.c:2536: Test failed: unexpected error code -559038737
locale.c:2627: Test failed: Expected lcid == 0, got 00001000, error -559038737
locale.c:4363: Test failed: IsValidLocaleName should have failed
locale.c:4365: Test failed: IsValidLocaleName should have failed
locale.c:4748: Test failed: For id 7, expected ret == 4, got 1, error 87
locale.c:4750: Test failed: For id 7, Expected IVC, got ''