README: remove wrong config name

There is no CONFIG_PCA953X_INFO symbol.
U-Boot uses CONFIG_CMD_PCA953X_INFO instead, which is described in
"Monitor Functions" section and thus no need to be repeated in the
"GPIO Support" section.
Remove the whole line.

Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
diff --git a/README b/README
index a4a450e..8e19aebb 100644
--- a/README
+++ b/README
@@ -1033,7 +1033,6 @@
 
 - GPIO Support:
 		CONFIG_PCA953X		- use NXP's PCA953X series I2C GPIO
-		CONFIG_PCA953X_INFO	- enable pca953x info command
 
 		The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
 		chip-ngpio pairs that tell the PCA953X driver the number of