huffyuvdsp: Enable the altivec code for PPC little-endian as well

Confirmed to work by checkasm.

libavcodec/ppc/huffyuvdsp_altivec.c

@@ -32,7 +32,7 @@
 #include "libavutil/ppc/util_altivec.h"
 #include "libavcodec/huffyuvdsp.h"
 
-#if HAVE_ALTIVEC && HAVE_BIGENDIAN
+#if HAVE_ALTIVEC
 static void add_bytes_altivec(uint8_t *dst, uint8_t *src, int w)
 {
     register int i;
@@ -49,14 +49,14 @@ static void add_bytes_altivec(uint8_t *dst, uint8_t *src, int w)
     for (; i < w; i++)
         dst[i] = src[i];
 }
-#endif /* HAVE_ALTIVEC && HAVE_BIGENDIAN */
+#endif /* HAVE_ALTIVEC */
 
 av_cold void ff_huffyuvdsp_init_ppc(HuffYUVDSPContext *c)
 {
-#if HAVE_ALTIVEC && HAVE_BIGENDIAN
+#if HAVE_ALTIVEC
     if (!PPC_ALTIVEC(av_get_cpu_flags()))
         return;
 
     c->add_bytes = add_bytes_altivec;
-#endif /* HAVE_ALTIVEC && HAVE_BIGENDIAN */
+#endif /* HAVE_ALTIVEC */
 }