scsi: fix Sparse warning: Initializer entry defined twice

Both REWIND and REZERO_UNIT use 0x01, READ_POSITION and PRE_FETCH
share 0x34.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/hw/scsi-bus.c b/hw/scsi-bus.c
index 736e91e..a2f9cc1 100644
--- a/hw/scsi-bus.c
+++ b/hw/scsi-bus.c
@@ -374,6 +374,7 @@
     static const char *names[] = {
         [ TEST_UNIT_READY          ] = "TEST_UNIT_READY",
         [ REZERO_UNIT              ] = "REZERO_UNIT",
+        /* REWIND and REZERO_UNIT use the same operation code */
         [ REQUEST_SENSE            ] = "REQUEST_SENSE",
         [ FORMAT_UNIT              ] = "FORMAT_UNIT",
         [ READ_BLOCK_LIMITS        ] = "READ_BLOCK_LIMITS",
@@ -409,7 +410,7 @@
         [ SEARCH_LOW               ] = "SEARCH_LOW",
         [ SET_LIMITS               ] = "SET_LIMITS",
         [ PRE_FETCH                ] = "PRE_FETCH",
-        [ READ_POSITION            ] = "READ_POSITION",
+        /* READ_POSITION and PRE_FETCH use the same operation code */
         [ SYNCHRONIZE_CACHE        ] = "SYNCHRONIZE_CACHE",
         [ LOCK_UNLOCK_CACHE        ] = "LOCK_UNLOCK_CACHE",
         [ READ_DEFECT_DATA         ] = "READ_DEFECT_DATA",
@@ -443,7 +444,6 @@
         [ SEND_VOLUME_TAG          ] = "SEND_VOLUME_TAG",
         [ WRITE_LONG_2             ] = "WRITE_LONG_2",
 
-        [ REWIND                   ] = "REWIND",
         [ REPORT_DENSITY_SUPPORT   ] = "REPORT_DENSITY_SUPPORT",
         [ GET_CONFIGURATION        ] = "GET_CONFIGURATION",
         [ READ_16                  ] = "READ_16",