get_bits: add get_bitsz for reading 0-25 bits

This can be used to simplify code in a couple of places.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>

libavcodec/get_bits.h

@@ -269,6 +269,14 @@ static inline unsigned int get_bits(GetBitContext *s, int n)
     return tmp;
 }
 
+/**
+ * Read 0-25 bits.
+ */
+static av_always_inline int get_bitsz(GetBitContext *s, int n)
+{
+    return n ? get_bits(s, n) : 0;
+}
+
 static inline unsigned int get_bits_le(GetBitContext *s, int n)
 {
     register int tmp;

libavcodec/mpegaudiodec_template.c

@@ -816,13 +816,6 @@ static void exponents_from_scale_factors(MPADecodeContext *s, GranuleDef *g,
     }
 }
 
-/* handle n = 0 too */
-static inline int get_bitsz(GetBitContext *s, int n)
-{
-    return n ? get_bits(s, n) : 0;
-}
-
-
 static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos,
                           int *end_pos2)
 {