e1000e: fix compiler warnings

This patch is to fix a compiler warning of __bad_udelay due to a value
of >999 being passed as a parameter to udelay() in the function
e1000e_phy_has_link_generic().  This affects the gcc compiler when
it is given a flag of -O3 and the icc compiler.

This patch is also making the change from mdelay() to msleep() in the
same function, since it was determined though code inspection that this
function is never called in atomic context.

Signed-off-by: David Ertman <davidx.m.ertman@intel.com>
Acked-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>