gralloc: Add allocation support for sRGB formats

Refer to graphics.h for the definition of these new formats.
The HWC doesn't yet support output to these formats.

Change-Id: I14dade3412d262d853d3783ba77d559c76d331bf
(cherry picked from commit 3a63837a3d006aee3d176d379409bf3134f6189b)
diff --git a/libgralloc/gpu.cpp b/libgralloc/gpu.cpp
index aacb18c..2b123dd 100644
--- a/libgralloc/gpu.cpp
+++ b/libgralloc/gpu.cpp
@@ -173,7 +173,7 @@
 {
     *bufferType = BUFFER_TYPE_VIDEO;
 
-    if (inputFormat < 0x7) {
+    if (inputFormat <= HAL_PIXEL_FORMAT_sRGB_888) {
         // RGB formats
         *bufferType = BUFFER_TYPE_UI;
     } else if ((inputFormat == HAL_PIXEL_FORMAT_R_8) ||