Revert r356077, apparently the change doesn't work after all (failed to

build in CI).

sys/conf/Makefile.riscv

@@ -28,10 +28,10 @@ S=	../../..
 
 INCLUDES+= -I$S/contrib/libfdt
 
-# XXX Make text segments writable.  This has historically been set for
-# riscv, but some preliminary testing shows it may not be needed; this
-# can likely be removed after some more testing.
-LDFLAGS+= -N
+SYSTEM_LD= @${LD} -N -m ${LD_EMULATION} -Bdynamic -T ${LDSCRIPT} ${_LDFLAGS} \
+	--no-warn-mismatch --warn-common --export-dynamic \
+	--dynamic-linker /red/herring \
+	-o ${.TARGET} -X ${SYSTEM_OBJS} vers.o
 
 .if !empty(DDB_ENABLED)
 CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls