powerpc/iseries: Fix constant warning

Fix smatch warning: constant 0x8000000000000000 is so big it is unsigned long
Signed-off-by: NDenis Kirjanov <dkirjanov@kernel.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/abs_addr.h

@@ -69,7 +69,7 @@ static inline unsigned long phys_to_abs(unsigned long pa)
  * Legacy iSeries Hypervisor calls
  */
 #define iseries_hv_addr(virtaddr)	\
-	(0x8000000000000000 | virt_to_abs(virtaddr))
+	(0x8000000000000000UL | virt_to_abs(virtaddr))
 
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_ABS_ADDR_H */