dct/rdft: Remove duplicate typedefs for context structs

The typedefs also exist in the avfft.h header and since typedefs cannot be
legally redefined in C, the code fails to compile with some compilers.

This reverts commits 11c7155c and 57f1b1dc.

libavcodec/dct.h

@@ -28,7 +28,7 @@
 
 #include "rdft.h"
 
-typedef struct DCTContext {
+struct DCTContext {
     int nbits;
     int inverse;
     RDFTContext rdft;
@@ -36,7 +36,7 @@ typedef struct DCTContext {
     FFTSample *csc2;
     void (*dct_calc)(struct DCTContext *s, FFTSample *data);
     void (*dct32)(FFTSample *out, const FFTSample *in);
-} DCTContext;
+};
 
 /**
  * Set up DCT.

libavcodec/fft-test.c

@@ -39,9 +39,11 @@
 #include "libavutil/mathematics.h"
 #include "libavutil/time.h"
 
-#include "dct.h"
 #include "fft.h"
+#if FFT_FLOAT
+#include "dct.h"
 #include "rdft.h"
+#endif
 
 /* reference fft */
 

libavcodec/rdft.h

@@ -48,7 +48,7 @@ extern SINTABLE(16384);
 extern SINTABLE(32768);
 extern SINTABLE(65536);
 
-typedef struct RDFTContext {
+struct RDFTContext {
     int nbits;
     int inverse;
     int sign_convention;
@@ -58,7 +58,7 @@ typedef struct RDFTContext {
     SINTABLE_CONST FFTSample *tsin;
     FFTContext fft;
     void (*rdft_calc)(struct RDFTContext *s, FFTSample *z);
-} RDFTContext;
+};
 
 /**
  * Set up a real FFT.