ata: libata-core: Remove unused function

Remove the function ata_do_simple_cmd() that is not used anywhere.

This was partially found by using a static code analysis program called cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Tejun Heo <tj@kernel.org>

drivers/ata/libata-core.c

@@ -1751,33 +1751,6 @@ unsigned ata_exec_internal(struct ata_device *dev,
 				    timeout);
 }
 
-/**
- *	ata_do_simple_cmd - execute simple internal command
- *	@dev: Device to which the command is sent
- *	@cmd: Opcode to execute
- *
- *	Execute a 'simple' command, that only consists of the opcode
- *	'cmd' itself, without filling any other registers
- *
- *	LOCKING:
- *	Kernel thread context (may sleep).
- *
- *	RETURNS:
- *	Zero on success, AC_ERR_* mask on failure
- */
-unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
-{
-	struct ata_taskfile tf;
-
-	ata_tf_init(dev, &tf);
-
-	tf.command = cmd;
-	tf.flags |= ATA_TFLAG_DEVICE;
-	tf.protocol = ATA_PROT_NODATA;
-
-	return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
-}
-
 /**
  *	ata_pio_need_iordy	-	check if iordy needed
  *	@adev: ATA device

drivers/ata/libata.h

@@ -76,7 +76,6 @@ extern unsigned ata_exec_internal_sg(struct ata_device *dev,
 				     struct ata_taskfile *tf, const u8 *cdb,
 				     int dma_dir, struct scatterlist *sg,
 				     unsigned int n_elem, unsigned long timeout);
-extern unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd);
 extern int ata_wait_ready(struct ata_link *link, unsigned long deadline,
 			  int (*check_ready)(struct ata_link *link));
 extern int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,