serial: pl010 is no longer broken

As more ARM platforms are moving into ARCH_MULTIPLATFORM, we can now
have integrator and versatile in the same kernel, and first one selects
this driver, causing a Kconfig warning:

warning: (ARCH_INTEGRATOR_AP) selects SERIAL_AMBA_PL010 which has unmet direct dependencies (TTY && HAS_IOMEM && ARM_AMBA && (BROKEN || !ARCH_VERSATILE))

It turns out that it has not been broken on versatile for a long time,
so we can remove the statement here.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>