Revert "gst1-libav: fix build for xtensa"

This reverts commit ae3298d7d489f5ee465ff4ce83494de527d0ac73.
Now that -mtext-section-literals is specified in the xtensa ABI this fix
is no longer needed.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/gstreamer1/gst1-libav/gst1-libav.mk

@@ -83,12 +83,4 @@ endif
 GST1_LIBAV_CONF_OPT = \
 	--with-libav-extra-configure="$(GST1_LIBAV_CONF_EXTRA_OPT)"
 
-GST1_LIBAV_CFLAGS = $(TARGET_CFLAGS)
-
-ifeq ($(BR2_xtensa),y)
-GST1_LIBAV_CFLAGS += -mtext-section-literals
-endif
-
-GST1_LIBAV_CONF_ENV += CFLAGS="$(GST1_LIBAV_CFLAGS)"
-
 $(eval $(autotools-package))