BUG: Fix include path detection with SDLDIR env var (issue #9086).

Also removed some superfluous search paths.

Modules/FindSDL.cmake

@@ -55,26 +55,18 @@
 FIND_PATH(SDL_INCLUDE_DIR SDL.h
   HINTS
   $ENV{SDLDIR}
-  PATH_SUFFIXES include
+  PATH_SUFFIXES include/SDL include
   PATHS
   ~/Library/Frameworks
   /Library/Frameworks
-  /usr/local/include/SDL
-  /usr/include/SDL
   /usr/local/include/SDL12
   /usr/local/include/SDL11 # FreeBSD ports
   /usr/include/SDL12
   /usr/include/SDL11
-  /usr/local/include
-  /usr/include
-  /sw/include/SDL # Fink
-  /sw/include
-  /opt/local/include/SDL # DarwinPorts
-  /opt/local/include
-  /opt/csw/include/SDL # Blastwave
-  /opt/csw/include 
-  /opt/include/SDL
-  /opt/include
+  /sw # Fink
+  /opt/local # DarwinPorts
+  /opt/csw # Blastwave
+  /opt
 )
 #MESSAGE("SDL_INCLUDE_DIR is ${SDL_INCLUDE_DIR}")
 
@@ -86,8 +78,6 @@ FIND_LIBRARY(SDL_LIBRARY_TEMP
   $ENV{SDLDIR}
   PATH_SUFFIXES lib64 lib
   PATHS
-  /usr/local
-  /usr
   /sw
   /opt/local
   /opt/csw
@@ -108,8 +98,6 @@ IF(NOT SDL_BUILDING_LIBRARY)
       $ENV{SDLDIR}
       PATH_SUFFIXES lib64 lib
       PATHS
-      /usr/local
-      /usr
       /sw
       /opt/local
       /opt/csw