staging: ccree: remove unused field

Field monitor_null_cycles of struct drvdata was not being used.
Remove it.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ccree/ssi_driver.h

@@ -125,10 +125,6 @@ struct ssi_drvdata {
 	int irq;
 	u32 irq_mask;
 	u32 fw_ver;
-	/* Calibration time of start/stop
-	 * monitor descriptors
-	 */
-	u32 monitor_null_cycles;
 	struct platform_device *plat_dev;
 	ssi_sram_addr_t mlli_sram_addr;
 	void *buff_mgr_handle;