pkg-config on MSYS

[lode leroy]

I have used the following modifications to get pkg-config working on MSYS
MSYS uses C:/some/path instead of C:\some\path
This patch makes it work on both msys and windows.

$ diff pkg-config-0.19-orig/parse.c pkg-config-0.19
1000c1000,1001
<         gchar *prefix = pkg->pcfiledir;
---
>         gchar *prefix = g_strdup(pkg->pcfiledir);
>
1002c1003
<         const char *const lib_pkgconfig = "\\lib\\pkgconfig";
---
>         const char *const lib_pkgconfig = "/lib/pkgconfig";
1004,1015c1005
<
<         if (strlen (prefix) > lib_pkgconfig_len &&
<             g_ascii_strcasecmp (prefix + prefix_len - lib_pkgconfig_len,
<                                 lib_pkgconfig) == 0)
<           {
<             /* It ends in lib\pkgconfig. Good. */
<
<             gchar *p;
<
<             prefix = g_strdup (prefix);
<             prefix[prefix_len - lib_pkgconfig_len] = '\0';
<
---
>         gchar *p;
1026a1017,1027
>
>         if (strlen (prefix) > lib_pkgconfig_len &&
>             g_ascii_strcasecmp (prefix + prefix_len - lib_pkgconfig_len,
>                                 lib_pkgconfig) == 0)
>           {
>             /* It ends in lib\pkgconfig. Good. */
>                                     prefix = g_strdup (prefix);
>             prefix[prefix_len - lib_pkgconfig_len] = '\0';
>