net: stmmac: Fix mixed enum type warning

The commit 5a5586112b92 ("net: stmmac: support FPE link partner
hand-shaking procedure") introduced the following coverity warning:

"Parse warning (PW.MIXED_ENUM_TYPE)"
"1. mixed_enum_type: enumerated type mixed with another type"

This is due to both "lo_state" and "lp_sate" which their datatype are
enum stmmac_fpe_state type, and being assigned with "FPE_EVENT_UNKNOWN"
which is a macro-defined of 0. Fixed this by assigned both these
variables with the correct enum value.

Fixes: 5a5586112b92 ("net: stmmac: support FPE link partner hand-shaking procedure")
Signed-off-by: Wong Vee Khee <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

···
 	if (is_up && *hs_enable) {
 		stmmac_fpe_send_mpacket(priv, priv->ioaddr, MPACKET_VERIFY);
 	} else {
-		*lo_state = FPE_EVENT_UNKNOWN;
-		*lp_state = FPE_EVENT_UNKNOWN;
+		*lo_state = FPE_STATE_OFF;
+		*lp_state = FPE_STATE_OFF;
 	}
 }