add missing strcasestr checks to cmake and autotools build systems,

and update config files.

include/SDL_config.h.cmake

@@ -140,6 +140,7 @@
 #cmakedefine HAVE_STRCASECMP 1
 #cmakedefine HAVE__STRNICMP 1
 #cmakedefine HAVE_STRNCASECMP 1
+#cmakedefine HAVE_STRCASESTR 1
 #cmakedefine HAVE_SSCANF 1
 #cmakedefine HAVE_VSSCANF 1
 #cmakedefine HAVE_VSNPRINTF 1

include/SDL_config.h.in

@@ -143,6 +143,7 @@
 #undef HAVE_STRCASECMP
 #undef HAVE__STRNICMP
 #undef HAVE_STRNCASECMP
+#undef HAVE_STRCASESTR
 #undef HAVE_SSCANF
 #undef HAVE_VSSCANF
 #undef HAVE_SNPRINTF

include/SDL_config_android.h

@@ -85,6 +85,7 @@
 #define HAVE_STRNCMP    1
 #define HAVE_STRCASECMP 1
 #define HAVE_STRNCASECMP 1
+#define HAVE_STRCASESTR 1
 #define HAVE_VSSCANF 1
 #define HAVE_VSNPRINTF  1
 #define HAVE_ACOS   1

include/SDL_config_iphoneos.h

@@ -85,6 +85,7 @@
 #define HAVE_STRNCMP    1
 #define HAVE_STRCASECMP 1
 #define HAVE_STRNCASECMP 1
+#define HAVE_STRCASESTR 1
 #define HAVE_VSSCANF 1
 #define HAVE_VSNPRINTF  1
 #define HAVE_M_PI   1

include/SDL_config_macosx.h

@@ -88,6 +88,7 @@
 #define HAVE_STRNCMP    1
 #define HAVE_STRCASECMP 1
 #define HAVE_STRNCASECMP 1
+#define HAVE_STRCASESTR 1
 #define HAVE_VSSCANF 1
 #define HAVE_VSNPRINTF  1
 #define HAVE_M_PI   1