The Marvell 88E6063 ethernet switch driver depends on the DSA
framework. Add a 'depends on NET_DSA' statement to its Kconfig
entry to state that explicitly.
Fixes the following Kconfig warning:
warning: (NET_DSA_MV88E6060 && NET_DSA_MV88E6063) selects NET_DSA_TAG_TRAILER which has unmet direct dependencies (NET && NET_DSA)
Signed-off-by: Gabor Juhos <juhosg@freemail.hu>