gpu: nvgpu: handle falcon copy pointer alignment for misra 11.3 deviation

Function for copying to/form IMEM/DMEM cast pointer to char to
pointer to u32 since falcon data registers are read/written in
4-bytes. Firmware data is generally byte stream and hence we
won't be able to deal in pointer to u32. Hence we need deviate
from misra rule 11.3.
Firmware data is also not aligned at word boundary sometimes
hence we need to copy it byte by byte to conform to the dev-
iation recommendation.

Error: MISRA C-2012 Rule 11.3: ./hal/falcon/falcon_gk20a.c:296:
misra_violation: The object pointer expression "src" of type
"u8 *" is cast to type "u32 *".

JIRA NVGPU-3271

Change-Id: Ic081f97226dbbcf08402970829624933402066eb
Signed-off-by: Sagar Kamble <skamble@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2108547
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svc-mobile-misra <svc-mobile-misra@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Mahantesh Kumbar <mkumbar@nvidia.com>
Reviewed-by: Vijayakumar Subbu <vsubbu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/common/utils/string.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2018-2019, NVIDIA CORPORATION.  All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -77,3 +77,13 @@ int nvgpu_strnadd_u32(char *dst, const u32 value, size_t size, u32 radix)
 
 	return n;
 }
+
+bool nvgpu_mem_is_word_aligned(struct gk20a *g, u8 *addr)
+{
+	if ((unsigned long)addr % 4UL != 0UL) {
+		nvgpu_log_info(g, "addr (%p) not 4-byte aligned", addr);
+		return false;
+	}
+
+	return true;
+}