scsi: aha152x: rename the PCMCIA define

We plan to enable building the PCMCIA core and drivers, and the
non-prefixed PCMCIA name clashes with some arch headers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>