generic: drop 704-phy-no-genphy-soft-reset.patch

generic: drop 704-phy-no-genphy-soft-reset.patch

4.4.80+ contains 71a165f6397df07a06ce643de5c2dbae29bd3cfb, 4.9.41+ contains
6c78197e4a69c19e61dfe904fdc661b2aee8ec20 which are all backports of upstream
commit 0878fff1f42c18e448ab5b8b4f6a3eb32365b5b6 ("net: phy: Do not perform
software reset for Generic PHY").

Our local patch is no longer needed, all this patch was doing was utilizing
gen10g_soft_reset which does nothing either, so just keep the code unchanged.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>