Adjust iteration counts so benchmarks don't run too slowly or quickly.
Ensure benchmarks take less than 10 seconds on older, slower cores and
more than 0.5 seconds on fast cores.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

memset with zero as the value to set is by far the majority value (99%+
for Python3 and GCC).  Add bench-memset-zero-large.c,
bench-memset-zero-walk.c and bench-memset-zero.c to measure memset
implementations for zeroing.

Reviewed-by: Sunil K Pandey <skpgkp2@gmail.com>

Add bench-bzero-large.c, bench-bzero-walk.c and bench-bzero.c.

Continue cleanup of the string benchtests.  Remove simplistic
byte-oriented versions with faster generic implementations.
Remove bcopy/bzero benchmarks (bcopy/bzero are obsolete and never
emitted by compilers).  Remove builtin versions of memcpy, memset
and strlen.  Remove all remaining "stupid" implementations given
they are always slower than the "simple" variants and thus don't
add anything useful.

	* benchtests/bench-strcasecmp.c (stupid_strcasecmp): Remove.
	* benchtests/bench-strcasestr.c (stupid_strcasestr): Remove.
	* benchtests/bench-strchr.c (stupid_strchr): Remove.
	* benchtests/bench-strcmp.c (stupid_strcmp): Remove.
	* benchtests/bench-strcspn.c (stupid_strcspn): Remove.
	* benchtests/bench-strlen.c (builtin_strlen): Remove.
	* benchtests/bench-strncasecmp.c (stupid_strncasecmp): Remove.
	* benchtests/bench-strncmp.c (stupid_strncmp): Remove.
	* benchtests/bench-strpbrk.c (stupid_strpbrk): Remove.
	* benchtests/bench-strspn.c (stupid_strspn): Remove.
	* benchtests/Makefile: Remove bench-bcopy.c and bench-bzero.c.
	* benchtests/bench-bcopy.c: Delete file.
	* benchtests/bench-bzero.c: Likewise.
	* benchtests/bench-memccpy.c (stupid_memccpy): Remove.
	(simple_memccpy): Remove.
	(generic_memccpy): Add function.
	* benchtests/bench-memcpy.c: (builtin_memcpy): Remove.
	* benchtests/bench-memmove.c (simple_bcopy): Remove.
	* benchtests/bench-mempcpy.c (simple_mempcpy): Remove.
	(generic_mempcpy): Add new function.
	* benchtests/bench-memset.c (simple_bzero): Remove.
	(builtin_bzero): Remove.
	(builtin_memset): Remove.
	* benchtests/bench-rawmemchr.c (simple_rawmemchr): Remove.
	(generic_rawmemchr): Add new function.

	* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.

	* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.