Remove DECLARE_ALIGNED_{8,16} macros

These macros are redundant.  All uses are replaced with the generic
DECLARE_ALIGNED macro instead.

Originally committed as revision 22233 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/mimic.c

@@ -45,7 +45,7 @@ typedef struct {
     AVFrame         buf_ptrs    [16];
     AVPicture       flipped_ptrs[16];
 
-    DECLARE_ALIGNED_16(DCTELEM, dct_block)[64];
+    DECLARE_ALIGNED(16, DCTELEM, dct_block)[64];
 
     GetBitContext   gb;
     ScanTable       scantable;