MFC r267436-267439:

- Replace malloc+memset with calloc.
- iconv_open(3): initialise ci_ilseq_invalid field of _citrus_iconv_shared
struct after allocation with malloc.
- iconvlist(3): reduce a memory leak by copying strings only once.
- iconv(1):
- Make invalids variable local to do_conv such that it prints the number
of invalid characters of the current file instead of an accumulated
value.
- Make do_conv return an error when invalid characters have been found.
Return EXIT_FAILURE from main if any file contained invalid characters.
This matches the behaviour of GNU iconv.
- Mark usage with __dead2 attribute.
- Make the long_options array const.

Tested by: Pavel Timofeev <timp87@gmail.com>

MFC r263986:

- In the libiconv module for ISO 2022 restore the original order of the
fields of a private struct such that variables of this type are
initialised correctly. Fixes conversion from ISO 2022.
Also do this in the BIG5 module to prevent similar errors in the future.
- In the libiconv module for EUC-TW replace 2^cs with 1<<cs. Fixes
conversion from EUC-TW.
- Synchronise iconv code with NetBSD. In most cases this only updates
the RCS id because the changes are already there or are NetBSD specific.
+ libc/iconv/citrus_csmapper.c: Add a comment.
+ libc/iconv/citrus_db_factory.c: Remove put16().
+ libc/iconv/citrus_iconv.c: Return EINVAL on error.
+ libc/iconv/citrus_mapper.c: Return EINVAL on error.
+ libc/iconv/citrus_memstream.c: Fix type of a variable.
+ libc/iconv/citrus_prop.h: Sync definition of _CITRUS_PROP_HINT_END.
+ libc/iconv/citrus_stdenc.c: Return EINVAL on error.
+ libiconv_modules/mapper_std/citrus_mapper_std.c: Plug memory leak.

Obtained from: NetBSD

MFC r267436-267439:

- Replace malloc+memset with calloc.
- iconv_open(3): initialise ci_ilseq_invalid field of _citrus_iconv_shared
struct after allocation with malloc.
- iconvlist(3): reduce a memory leak by copying strings only once.
- iconv(1):
- Make invalids variable local to do_conv such that it prints the number
of invalid characters of the current file instead of an accumulated
value.
- Make do_conv return an error when invalid characters have been found.
Return EXIT_FAILURE from main if any file contained invalid characters.
This matches the behaviour of GNU iconv.
- Mark usage with __dead2 attribute.
- Make the long_options array const.

Tested by: Pavel Timofeev <timp87@gmail.com>

MFC r263986:

- In the libiconv module for ISO 2022 restore the original order of the
fields of a private struct such that variables of this type are
initialised correctly. Fixes conversion from ISO 2022.
Also do this in the BIG5 module to prevent similar errors in the future.
- In the libiconv module for EUC-TW replace 2^cs with 1<<cs. Fixes
conversion from EUC-TW.
- Synchronise iconv code with NetBSD. In most cases this only updates
the RCS id because the changes are already there or are NetBSD specific.
+ libc/iconv/citrus_csmapper.c: Add a comment.
+ libc/iconv/citrus_db_factory.c: Remove put16().
+ libc/iconv/citrus_iconv.c: Return EINVAL on error.
+ libc/iconv/citrus_mapper.c: Return EINVAL on error.
+ libc/iconv/citrus_memstream.c: Fix type of a variable.
+ libc/iconv/citrus_prop.h: Sync definition of _CITRUS_PROP_HINT_END.
+ libc/iconv/citrus_stdenc.c: Return EINVAL on error.
+ libiconv_modules/mapper_std/citrus_mapper_std.c: Plug memory leak.

Obtained from: NetBSD