net: phy: Only call phy_init() on systems needing manual relocation

The phy_init() is now used only to perform manual relocation of PHY
driver callbacks. Wrap it in ifdeffery and only call it on systems
which still require manual relocation, i.e. m68k .

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Tested-by: Michal Simek <michal.simek@amd.com> #microblaze (MANUAL_RELOC)