net: fs_enet: Remove set but not used variable

net: fs_enet: Remove set but not used variable

CC      drivers/net/ethernet/freescale/fs_enet/fs_enet-main.o
drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c: In function 'fs_enet_interrupt':
drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c:321:40: warning: variable 'fpi' set but not used [-Wunused-but-set-variable]

Remove that variable.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/90b72c1708bb8ba2b7a1a688e8259e428968364d.1691155346.git.christophe.leroy@csgroup.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>