i2c: ismt: do not duplicate msi_enabled flag

struct pci_dev already has a flag to track if MSI is enabled or not. Use it
directly.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c
index 3889e6b..3cc20f3 100644
--- a/drivers/i2c/busses/i2c-ismt.c
+++ b/drivers/i2c/busses/i2c-ismt.c
@@ -172,7 +172,6 @@
 	u8 head;				/* ring buffer head pointer */
 	struct completion cmp;			/* interrupt completion */
 	u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1];	/* temp R/W data buffer */
-	bool using_msi;				/* type of interrupt flag */
 };
 
 /**
@@ -398,7 +397,7 @@
 	desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write);
 
 	/* Initialize common control bits */
-	if (likely(priv->using_msi))
+	if (likely(pci_dev_msi_enabled(priv->pci_dev)))
 		desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR;
 	else
 		desc->control = ISMT_DESC_FAIR;
@@ -806,7 +805,6 @@
 		goto intx;
 	}
 
-	priv->using_msi = true;
 	goto done;
 
 	/* Try using legacy interrupts */
@@ -822,8 +820,6 @@
 		return -ENODEV;
 	}
 
-	priv->using_msi = false;
-
 done:
 	return 0;
 }