hx4700: regulator: declare full constraints

Since the removal of CONFIG_REGULATOR_DUMMY option, the touchscreen stopped
working. This patch enables the "replacement" for REGULATOR_DUMMY and
allows the touchscreen to work even though there is no regulator for "vcc".

Cc: stable@vger.kernel.org
Signed-off-by: Martin Vajnar <martin.vajnar@gmail.com>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>

(cherry picked from commit a52d2093

)
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

arch/arm/mach-pxa/hx4700.c

@@ -891,6 +891,8 @@ static void __init hx4700_init(void)
 	mdelay(10);
 	gpio_set_value(GPIO71_HX4700_ASIC3_nRESET, 1);
 	mdelay(10);
+
+	regulator_has_full_constraints();
 }
 
 MACHINE_START(H4700, "HP iPAQ HX4700")