headers: Fix wrong return type for PathQuoteSpacesA and PathQuoteSpacesW

[1] describes PathQuoteSpacesA with return type BOOL and
[2] describes PathQuoteSpacesW with return type BOOL.

Both functions are currently declared with return type void in shlwapi.h.

Fix this by using LWSTDAPI_(WINBOOL) as return type similar to the other
functions in that header.

This fixes bug report 999. See [3].

[1]: https://learn.microsoft.com/en-us/windows/win32/api/shlwapi/nf-shlwapi-pathquotespacesa
[2]: https://learn.microsoft.com/en-us/windows/win32/api/shlwapi/nf-shlwapi-pathquotespacesw
[3]: https://sourceforge.net/p/mingw-w64/bugs/999/

Fixes: 9d937a7f4f76 ("Add mingw-w64 header set as initial set.")
Signed-off-by: Daniel Starke <daniel-email@gmx.net>
Signed-off-by: LIU Hao <lh_mouse@126.com>