sanders: Remove more deprecated display flags

Change-Id: I7924f76ed864dea9cefbe2585be629bd2239c447
Signed-off-by: ashwatthama <sai404142@gmail.com>

BoardConfig.mk

@@ -173,9 +173,6 @@ TARGET_USES_C2D_COMPOSITION := true
 TARGET_USES_GRALLOC1 := true
 TARGET_USES_ION := true
 TARGET_USES_HWC2 := true
-TARGET_USES_NEW_ION_API := true
-MAX_EGL_CACHE_KEY_SIZE := 12*1024
-MAX_EGL_CACHE_SIZE := 2048*1024
 MAX_VIRTUAL_DISPLAY_DIMENSION := 4096
 TARGET_FORCE_HWC_FOR_VIRTUAL_DISPLAYS := true
 TARGET_SCREEN_DENSITY := 450