[peerdist] Remove never-used peerdist_msg_blk() macro

The peerdist_msg_blk() macro seems to have been introduced in the
original commit that added pccrr.h, but this macro was never used by
the version of the code present in that commit.

Remove this unused macro and the corresponding nonexistent external
function declaration.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/include/ipxe/pccrr.h

@@ -12,7 +12,6 @@
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdint.h>
-#include <ipxe/uaccess.h>
 
 /** Magic retrieval URI path */
 #define PEERDIST_MAGIC_PATH "/116B50EB-ECE2-41ac-8429-9F9E963361B7/"
@@ -350,27 +349,4 @@ struct peerdist_msg_blk {
 /** Retrieval protocol block fetch response type */
 #define PEERDIST_MSG_BLK_TYPE 0x00000005UL
 
-/**
- * Parse retrieval protocol block fetch response
- *
- * @v raw		Raw data
- * @v raw_len		Length of raw data
- * @v digestsize	Digest size
- * @v blksize		Cipher block size
- * @v blk		Structure to fill in
- * @ret rc		Return status code
- */
-#define peerdist_msg_blk( raw, raw_len, digestsize, blksize, blk ) ( {	\
-	assert ( sizeof ( (blk)->segment.id ) == (digestsize) );	\
-	assert ( sizeof ( (blk)->block.data ) == 0 );			\
-	assert ( sizeof ( (blk)->vrf.data ) == 0 );			\
-	assert ( sizeof ( (blk)->iv.data ) == blksize );		\
-	peerdist_msg_blk_untyped ( (raw), (raw_len), (digestsize),	\
-				   (blksize), blk );			\
-	} )
-
-extern int peerdist_msg_blk_untyped ( userptr_t raw, size_t raw_len,
-				      size_t digestsize, size_t blksize,
-				      void *out );
-
 #endif /* _IPXE_PCCRR_H */