libvpx: Pull from upstream

source/libvpx/build/make/configure.sh

Index: source/libvpx/build/make/configure.sh
===================================================================
--- source/libvpx/build/make/configure.sh	(revision 232232)
+++ source/libvpx/build/make/configure.sh	(working copy)
@@ -1060,9 +1060,11 @@
                 CC=${CC:-icc}
                 LD=${LD:-icc}
                 setup_gnu_toolchain
-                add_cflags -use-msasm -use-asm
-                add_ldflags -i-static
-                enabled x86_64 && add_cflags -ipo -no-prec-div -static -xSSE2 -axSSE2
+                add_cflags -use-msasm  # remove -use-msasm too?
+                # add -no-intel-extensions to suppress warning #10237
+                # refer to http://software.intel.com/en-us/forums/topic/280199
+                add_ldflags -i-static -no-intel-extensions
+                enabled x86_64 && add_cflags -ipo -static -O3 -no-prec-div
                 enabled x86_64 && AR=xiar
                 case ${tune_cpu} in
                     atom*)
@@ -1106,6 +1108,18 @@
             soft_enable sse4_1
         fi
 
+        if enabled gcc && ! disabled avx && ! check_cflags -mavx; then
+            RTCD_OPTIONS="${RTCD_OPTIONS}--disable-avx "
+        else
+            soft_enable avx
+        fi
+
+        if enabled gcc && ! disabled avx2 && ! check_cflags -mavx2; then
+            RTCD_OPTIONS="${RTCD_OPTIONS}--disable-avx2 "
+        else
+            soft_enable avx2
+        fi
+
         case "${AS}" in
             auto|"")
                 which nasm >/dev/null 2>&1 && AS=nasm