pcmcia/axnet_cs: make use of 'max()' instead of handcrafted one

Use 'max(x,y)' instead of 'x < y ? y : x'.

Signed-off-by: Richard Knutsson <ricknu-0@student.ltu.se>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>