riscv64 libc string support,

adopted from aarch64, no native ffs() for now, use C version.
after corrections from kettenis@

diff --git a/lib/libc/arch/riscv64/string/Makefile.inc b/lib/libc/arch/riscv64/string/Makefile.inc
new file mode 100644 (file)
index 0000000..22940ae
--- /dev/null
+++ b/lib/libc/arch/riscv64/string/Makefile.inc
@@ -0,0 +1,9 @@
+# $OpenBSD: Makefile.inc,v 1.1 2021/04/28 04:26:40 drahn Exp $
+
+SRCS+= bcopy.c memcpy.c memmove.c \
+       strchr.c strrchr.c \
+       bcmp.c bzero.c ffs.c memchr.c memcmp.c memset.c \
+       strcmp.c strncmp.c \
+       strcat.c strcpy.c strcspn.c strlen.c strlcat.c strlcpy.c \
+       strncat.c  strncpy.c strpbrk.c strsep.c \
+       strspn.c swab.c strstr.c