crypto: scatterwalk - remove duplicate function declarations

scatterwalk_map() is an inline function already defined in the
header file, it is necessary to delete the re-declaration at the
same location, which was left out in the header file by an
earlier modification.
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

include/crypto/scatterwalk.h

@@ -93,7 +93,6 @@ static inline void scatterwalk_done(struct scatter_walk *walk, int out,
 
 void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
 			    size_t nbytes, int out);
-void *scatterwalk_map(struct scatter_walk *walk);
 
 void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
 			      unsigned int start, unsigned int nbytes, int out);