graphics: remove unused const variable

This removes the constexpr const char * default_glesv1_lib and promote
-Wunused-const-variable back to error level on clang.

CMakeLists.txt

@@ -24,10 +24,6 @@ set(C_AND_CXX_WARNINGS "-pedantic -Wall -Wextra")
 set(EXTRA_C_WARNINGS "-Wcast-align -Wcast-qual -Wformat -Wredundant-decls -Wswitch-default")
 set(EXTRA_CXX_WARNINGS "-Wnon-virtual-dtor -Wold-style-cast")
 
-if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
-  set(EXTRA_CXX_WARNINGS "${EXTRA_CXX_WARNINGS} -Wno-error=unused-const-variable")
-endif()
-
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${C_AND_CXX_WARNINGS}")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${EXTRA_C_WARNINGS}")
 

src/anbox/graphics/emugl/RenderApi.cpp

@@ -30,7 +30,6 @@ GLESv1Dispatch s_gles1;
 
 namespace {
 constexpr const char *default_egl_lib{"libEGL.so.1"};
-constexpr const char *default_glesv1_lib{"libGLESv1_CM.so.1"};
 constexpr const char *default_glesv2_lib{"libGLESv2.so.2"};
 }