parisc: use generic atomic64 on 32-bit

Somewhat redundant since our atomic_t uses hashed-locks on 32-bit
anyway... Maybe we can clean those up to be generic too someday.

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index c38bbc7..06f8d5b 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -17,6 +17,7 @@
 	select INIT_ALL_POSSIBLE
 	select BUG
 	select HAVE_PERF_COUNTERS
+	select GENERIC_ATOMIC64 if !64BIT
 	help
 	  The PA-RISC microprocessor is designed by Hewlett-Packard and used
 	  in many of their workstations & servers (HP9000 700 and 800 series,