iommu/arm-smmu-v3: replace symbolic permissions by octal permissions for module parameter

This fixed the below checkpatch issue:
WARNING: Symbolic permissions 'S_IRUGO' are not preferred. Consider using
octal permissions '0444'.
417: FILE: drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:417:
module_param_named(disable_bypass, disable_bypass, bool, S_IRUGO);
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20200827092957.22500-2-song.bao.hua@hisilicon.comSigned-off-by: Will Deacon <will@kernel.org>

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

@@ -414,7 +414,7 @@
 #define MSI_IOVA_LENGTH			0x100000
 
 static bool disable_bypass = 1;
-module_param_named(disable_bypass, disable_bypass, bool, S_IRUGO);
+module_param_named(disable_bypass, disable_bypass, bool, 0444);
 MODULE_PARM_DESC(disable_bypass,
 	"Disable bypass streams such that incoming transactions from devices that are not attached to an iommu domain will report an abort back to the device and will not be allowed to pass through the SMMU.");