avcodec/lossless_videodsp: add missing call to ff_llviddsp_init_ppc()

Signed-off-by: James Almer <jamrial@gmail.com>

libavcodec/lossless_videodsp.c

@@ -107,6 +107,8 @@ void ff_llviddsp_init(LLVidDSPContext *c)
 
     c->add_left_pred_int16        = add_left_pred_int16_c;
 
+    if (ARCH_PPC)
+        ff_llviddsp_init_ppc(c);
     if (ARCH_X86)
         ff_llviddsp_init_x86(c);
 }