Fill buffer speed up

Eliminates the byte by byte read from bool decoder,  by reading
in a size_t and then shifting it into place.

Change-Id: I0ed8c7b6f942847e79cc90105dc1d2b5b3deb0d6
diff --git a/vpx_util/vpx_util.mk b/vpx_util/vpx_util.mk
index 1161125..c0ef8d3 100644
--- a/vpx_util/vpx_util.mk
+++ b/vpx_util/vpx_util.mk
@@ -11,3 +11,4 @@
 UTIL_SRCS-yes += vpx_util.mk
 UTIL_SRCS-yes += vpx_thread.c
 UTIL_SRCS-yes += vpx_thread.h
+UTIL_SRCS-yes += endian_inl.h