GPIO: pca953x: fix spelling in help

Signed-off-by: Laurence Withers <lwithers@guralp.com>

drivers/gpio/pca953x.c

@@ -287,7 +287,7 @@ U_BOOT_CMD(
 	"	- set pin as output and drive low or high\n"
 	"pca953x invert pin 0|1\n"
 	"	- disable/enable polarity inversion for reads\n"
-	"pca953x intput pin\n"
+	"pca953x input pin\n"
 	"	- set pin as input and read value"
 );