libc_data_t is 8 bytes wide, so a buffer which is 4-byte but not
8-byte aligned falls back to the byte at a time loop. Add a 32-bit
middle path so such buffers still handle four bytes per iteration.
* Add DETECTNULL32/DETECTCHAR32, UNALIGNED4/UNALIGNED4_X,
LITTLEBLOCKSIZE4/BIGBLOCKSIZE4 and TOO_SMALL4 to libs/libc/libc.h.
* Take the new path in memccpy, memcmp, memcpy, memset, stpcpy,
stpncpy, strcmp, strcpy, strncmp and strncpy when both pointers are
4-byte aligned but the 8-byte path can't be used.
Assisted-by: Claude:claude-opus-5
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
