remove hardcoded compiler optimizations and -g

Index: rts/lib/assimp/CMakeLists.txt
--- rts/lib/assimp/CMakeLists.txt.orig
+++ rts/lib/assimp/CMakeLists.txt
@@ -216,8 +216,8 @@ ENDIF()
 if (ASSIMP_COVERALLS)
     MESSAGE(STATUS "Coveralls enabled")
     INCLUDE(Coveralls)
-    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -O0 -fprofile-arcs -ftest-coverage")
-    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g -O0 -fprofile-arcs -ftest-coverage")
+    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fprofile-arcs -ftest-coverage")
+    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fprofile-arcs -ftest-coverage")
 endif()
 
 if (ASSIMP_WERROR)
