8139too: some style cleanups

Clean up the following errors and warnings reported by checkpatch.pl:
 + ERROR: Macros with complex values should be enclosed in parenthesis
 + WARNING: __func__ should be used instead of gcc specific __FUNCTION__
 + WARNING: plain inline is preferred over __inline__
 + WARNING: Use #include <linux/io.h> instead of <asm/io.h>
 + WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>

The changes were verified with by comparing the "objdump -d 8139too.ko"
output which is exactly the same for the old and new version in case of
config CONFIG_8139TOO=m, CONFIG_8139TOO_PIO=n, CONFIG_8139TOO_TUNE_TWISTER=n,
CONFIG_8139TOO_8129=n, CONFIG_8139_OLD_RX_RESET=n.
Software versions used: gcc 4.2.3, objdump 2.18.0.20080103, on elf32-i386.

Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>