scsi: jazz_esp: Only build if SCSI core is builtin

JAZZ_ESP is a bool kconfig symbol that selects SCSI_SPI_ATTRS.  When
CONFIG_SCSI=m, this results in SCSI_SPI_ATTRS=m while JAZZ_ESP=y, which
causes many undefined symbol linker errors.

Fix this by only offering to build this driver when CONFIG_SCSI=y.

[mkp: JAZZ_ESP is unique in that it does not support being compiled as a
module unlike the remaining SPI SCSI HBA drivers]

Fixes: 1da177e4

 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20240214055953.9612-1-rdunlap@infradead.org
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-mips@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202402112222.Gl0udKyU-lkp@intel.com/
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>