qadd is an armv5e instruction, check for an ARMv6+ instruction

(cherry picked from commit 552136938058e86d947a9eda6e63f2484e12dcea)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

configure.ac

@@ -1383,7 +1383,7 @@ AS_IF([test "${enable_neon}" != "no"], [
     AC_COMPILE_IFELSE([
       AC_LANG_PROGRAM(,[[
 asm volatile("vqmovun.s64 d0, q1":::"d0");
-asm volatile("qadd r0, r0, r0":::"r0"); /* assume ARMv6 */
+asm volatile("ssat r0, #1, r0":::"r0"); /* assume ARMv6 */
 ]])
     ], [
       ac_cv_neon_inline="-mfpu=neon"