phy: phy-core.c: remove unnecessary initialization of local variables

There were a few places where variables are initialized unncessarily.
Remove those initializations.

Change-Id: I0c4abb0f17cb630eb45e5d662d5c55ca1ac19087
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Git-commit: d18c960430ca341e5c12a023c805ff8fd10032a6
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>