irqchip/gic: Spelling s/REturn/Return/

Fix a capitalization typo.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201209101504.2206941-1-geert+renesas@glider.be

drivers/irqchip/irq-gic.c

@@ -973,7 +973,7 @@ void gic_migrate_target(unsigned int new_cpu_id)
 /*
  * gic_get_sgir_physaddr - get the physical address for the SGI register
  *
- * REturn the physical address of the SGI register to be used
+ * Return the physical address of the SGI register to be used
  * by some early assembly code when the kernel is not yet available.
  */
 static unsigned long gic_dist_physaddr;