Set CONFIG_LOWBITDEPTH default to 1

Change-Id: I87b20a41d79be4b9aca3872749db133d5e6134a5
diff --git a/build/cmake/aom_config_defaults.cmake b/build/cmake/aom_config_defaults.cmake
index a33b133..21726df 100644
--- a/build/cmake/aom_config_defaults.cmake
+++ b/build/cmake/aom_config_defaults.cmake
@@ -106,7 +106,7 @@
 set_aom_config_var(CONFIG_INSPECTION 0 NUMBER "Enables bitstream inspection.")
 set_aom_config_var(CONFIG_INTERNAL_STATS 0 NUMBER
                    "Enables internal encoder stats.")
-set_aom_config_var(CONFIG_LOWBITDEPTH 0 NUMBER
+set_aom_config_var(CONFIG_LOWBITDEPTH 1 NUMBER
                    "Enables 8-bit optimized pipeline.")
 set_aom_config_var(CONFIG_MAX_DECODE_PROFILE 2 NUMBER
                    "Max profile to support decoding.")