Re: [PATCH v4 0/5] MR5365: win32u: Introduce a new common vulkan source.

[Brendan Shanks (＠bshanks)]

Brendan Shanks (@bshanks) commented about configure.ac:
>  WINE_CHECK_SONAME(vulkan, vkGetInstanceProcAddr)
>  if test "x$ac_cv_lib_soname_vulkan" = "x"
>  then
> -
>    WINE_CHECK_SONAME(MoltenVK, vkGetInstanceProcAddr)
> -
>    WINE_CHECK_SONAME(MoltenVK, vkGetInstanceProcAddr, [AC_DEFINE_UNQUOTED(SONAME_LIBVULKAN,[$ac_cv_lib_soname_MoltenVK])])

This is causing build errors for me:
```
../dlls/win32u/vulkan.c:91:35: error: use of undeclared identifier 'libMoltenVK'
    if (!(vulkan_handle = dlopen( SONAME_LIBVULKAN, RTLD_NOW )))
                                  ^
include/config.h:773:26: note: expanded from macro 'SONAME_LIBVULKAN'
#define SONAME_LIBVULKAN libMoltenVK.dylib
                         ^
../dlls/win32u/vulkan.c:93:37: error: use of undeclared identifier 'libMoltenVK'
        ERR( "Failed to load %s\n", SONAME_LIBVULKAN );
                                    ^
include/config.h:773:26: note: expanded from macro 'SONAME_LIBVULKAN'
#define SONAME_LIBVULKAN libMoltenVK.dylib
                         ^
2 errors generated.
make[1]: *** [dlls/win32u/vulkan.o] Error 1
```

I think quotes are needed around `$ac_cv_lib_soname_MoltenVK`, that results in `SONAME_LIBVULKAN` being correctly quoted.