aarch64: vp9itxfm: Use the offset parameter to movrel

This fixes build failures for iOS, broken since cad42fad.
Signed-off-by: Martin Storsjö <martin@martin.st>

libavcodec/aarch64/vp9itxfm_neon.S

@@ -1108,7 +1108,7 @@ function ff_vp9_idct_idct_32x32_add_neon, export=1
 
         movrel          x10, idct_coeffs
         add             x11, x10, #32
-        movrel          x12, min_eob_idct_idct_32 + 2
+        movrel          x12, min_eob_idct_idct_32, 2
 
         mov             x15, x30