mxser_new, pci_request_region for pci regions

Use pci_request_region instead of standard request_region for pci device
regions.  More checking, simplier use.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>