ARM: OMAP: HSMMC: General code cleanup and cosmetic fixes

This patch makes the following general code cleanup and cosmetic fixes:

- Use #include <linux/io.h> instead of <asm/io.h>, according to warning
reported by scripts/checkpatch.pl on arch/arm/mach-omap2/board-sdp-hsmmc.c

- Use if (power_on) instead of if (power_on == 1).

- Use if (ret) instead of if (ret != 0).

- Add an extra-line to separate labels.

Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Acked-by: Anderson Lizardo <anderson.lizardo@indt.org.br>
Acked-by: Eduardo Valentin <eduardo.valentin@indt.org.br>
Signed-off-by: Tony Lindgren <tony@atomide.com>