MAINTAINERS: Add ST's Random Number Generator to the ST entry

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

MAINTAINERS

@@ -1521,6 +1521,7 @@ W:	http://www.stlinux.com
 S:	Maintained
 F:	arch/arm/mach-sti/
 F:	arch/arm/boot/dts/sti*
+F:	drivers/char/hw_random/st-rng.c
 F:	drivers/clocksource/arm_global_timer.c
 F:	drivers/clocksource/clksrc_st_lpc.c
 F:	drivers/i2c/busses/i2c-st.c