net/ixgbe/base: fix skipping PHY config

net/ixgbe/base: fix skipping PHY config

By exiting early we could skip the PHY configuration and as such
the driver may not configure the PHY correctly for SFP+.

This patch removes the logic which would previously skip the PHY
configuration in the case where we are already at the requested
speed in ixgbe_setup_mac_link_multispeed_fiber().

Fixes: f3430431abaf ("ixgbe/base: add SFP+ dual-speed support")
Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Acked-by: Wenzhuo Lu <wenzhuo.lu@intel.com>