ide: add ide_retry_pc() helper

* Add ide_create_request_sense_cmd() and ide_retry_pc() helpers
  and convert ide-{atapi,floppy,tape}.c to use them.

* Remove no longer used ide*_create_request_sense_cmd(),
  ide*_retry_pc() and 'retry_pc' argument from ide_pc_intr().

* Make ide_queue_pc_head() static.

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide-floppy.h

@@ -49,7 +49,6 @@ typedef struct ide_floppy_obj {
 /* ide-floppy.c */
 void ide_floppy_create_mode_sense_cmd(struct ide_atapi_pc *, u8);
 void ide_floppy_create_read_capacity_cmd(struct ide_atapi_pc *);
-void ide_floppy_create_request_sense_cmd(struct ide_atapi_pc *);
 
 /* ide-floppy_ioctl.c */
 int ide_floppy_format_ioctl(ide_drive_t *, struct file *, unsigned int,