mfd: fix comment

Signed-off-by: Antonio Ospite <[e-mail]>
Cc: Mika Westerberg <[e-mail]>
Cc: Samuel Ortiz <[e-mail]>
Signed-off-by: Jiri Kosina <[e-mail]>

drivers/mfd/intel_msic.c

···
 
 /*
  * MSIC interrupt tree is readable from SRAM at INTEL_MSIC_IRQ_PHYS_BASE.
- * Since IRQ block starts from address 0x002 we need to substract that from
+ * Since IRQ block starts from address 0x002 we need to subtract that from
  * the actual IRQ status register address.
  */
 #define MSIC_IRQ_STATUS(x)	(INTEL_MSIC_IRQ_PHYS_BASE + ((x) - 2))