Prevent bogus addition of -rpath to libraries.

CMakeLists.txt

@@ -72,6 +72,9 @@ IF(CMAKE_COMPILER_IS_GNUCC)
             ADD_DEFINITIONS(-fvisibility=hidden)
         ENDIF(NOT OS2 AND NOT SOLARIS AND NOT WINDOWS)
     ENDIF(PHYSFS_IS_GCC4)
+
+    # Don't use -rpath.
+    SET(CMAKE_SKIP_RPATH ON CACHE BOOL "Skip RPATH" FORCE)
 ENDIF(CMAKE_COMPILER_IS_GNUCC)
 
 IF(CMAKE_C_COMPILER_ID STREQUAL "SunPro")