crt: Provide emulation of ___lc_handle_func for msvcrt.dll and msvcrtd.dll

Ensure that the ___lc_handle_func symbol is available for all builds which
uses msvcrt.dll and msvcrtd.dll runtime DLLs. ___lc_handle_func() emulation
uses the global __lc_handle variable which is present in all msvcrt.dll and
msvcrtd.dll versions.

Signed-off-by: Martin Storsjö <martin@martin.st>