libmemtrack: Properly account for memory usage

Do not count the memory usage for egl_surfaces since its used
as egl_image in surface flinger.

Change-Id: If0049fb04ead93c632e3c4ad15185a19f17e0810
diff --git a/libmemtrack/kgsl.c b/libmemtrack/kgsl.c
index 3026175..b120246 100644
--- a/libmemtrack/kgsl.c
+++ b/libmemtrack/kgsl.c
@@ -113,7 +113,7 @@
                 unaccounted_size += size;
 
         } else if (type == MEMTRACK_TYPE_GRAPHICS && strcmp(line_type, "ion") == 0) {
-            if (!is_surfaceflinger || strcmp(line_usage, "egl_image") != 0) {
+            if ( !(is_surfaceflinger == false && strcmp(line_usage, "egl_surface") == 0)) {
                 unaccounted_size += size;
             }
         }