ARM: OMAP2+: Remove unneeded #include <linux/pinctrl/pinmux.h>

Commit 44c22a2d ("ARM: OMAP2+: pm33xx: Add support for rtc+ddr
in self refresh mode") added the include, but no user.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Message-Id: <7f22fb21f76f4d23be2e31a5908bcfa295704ef4.1668000965.git.geert+renesas@glider.be>
Signed-off-by: Tony Lindgren <tony@atomide.com>