ARM: imx: Drop imx_anatop_usb_chrg_detect_disable()

ARM: imx: Drop imx_anatop_usb_chrg_detect_disable()

With commit b5bbe2235361 ("usb: phy: mxs: Disable external charger
detect in mxs_phy_hw_init()") in tree all of the necessary charger
setup is done by the USB PHY driver which covers all of the affected
i.MX6 SoCs.

NOTE: imx_anatop_usb_chrg_detect_disable() was also called for i.MX7D,
but looking at its datasheet it appears to have a different USB PHY IP
block, so executing i.MX6 charger disable configuration seems
unnecessary.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: linux-imx@nxp.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>