ARM: dove: drop "select COMMON_CLK_DOVE"

Commit 5b03df9a ("ARM: dove: switch to
DT clock providers") added "select COMMON_CLK_DOVE" to Marvell Dove's
Kconfig entry. But there's no Kconfig symbol COMMON_CLK_DOVE, which
makes this select statement a nop. It's probably a leftover of some
experimental code that never hit mainline. Drop it.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>