ARM: 7216/1: mmc: mmci: Do not release spinlock in request_end

The patch "mmc: core: move ->request() call from atomic context",
is the reason to why this change is possible. This simplifies the
error handling code execution path quite a lot and potentially also
fixes some error handling hang problems.

Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>