microblaze: Use simple memmove/memcpy implementation from lib/string.c

This is based on previous commit ("microblaze: Use simple memset
implementation from lib/string.c") where generic memset implementation is
used when OPT_LIB_FUNCTION is not defined. The same change can be done for
memset/memcpy implementation where doesn't make sense to have generic
implementation in architecture code.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1f5cfc026a8a458f3e3134ab80f65bd4ac7e3e8e.1645797329.git.michal.simek@xilinx.com

microblaze: Use simple memset implementation from lib/string.c

On microblaze systems which are not using OPT_LIB_FUNCTION only simple
memset is used. This function is already implemented in lib/string.c that's
why it should be used instead.
This change is done in respect of issue fixed by commit 33d0f96ffd73
("lib/string.c: Use freestanding environment") where gcc-10.x moved
-ftree-loop-distribute-patterns optimization is to O2 optimization level.
This optimization causes GCC to convert the while loop in memset.c into a
call to memset. So This optimization is transforming a loop in a
memset/memcpy into a call to the function itself. This makes the memset
implementation as recursive.

Based on fix above -ffreestanding was used and it needs to be used on
Microblaze too but the patch is not adding this flag it removes simple
implementation to cause that generic implementation is used where this flag
is already setup.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mahesh Bodapati <mbodapat@xilinx.com>
Link: https://lore.kernel.org/r/4a143e7654f72ee893dcea9769946e17d3570b16.1645797329.git.michal.simek@xilinx.com

microblaze: Convert headers to SPDX license

Covert all headers to SPDX.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Stefan Asserhall <stefan.asserhall@xilinx.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

microblaze: Guard __HAVE_ARCH macros with __KERNEL__ in string.h

A polarity reversal in the __KERNEL__ guard prevents the __HAVE_ARCH
flags from being defined in kernel compilation.

I noticed that there's now an option for assembly-optimized versions of
memcpy and memmove. I believe this may be buggy; when I turn it on, all
my printk output gets smashed together, as if the newlines aren't getting
copied.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>

microblaze_v8: string.h thread_info.h

Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>