turn err into errx in lguest call sites

These two callsites should really be errx instead of err, since there is
no errno associated with them in the moment they are issued.
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Glauber de Oliveira Costa <gcosta@redhat.com>

Documentation/lguest/lguest.c

@@ -159,7 +159,7 @@ static unsigned long entry_point(void *start, void *end,
 		if (memcmp(p, "GenuineLguest", strlen("GenuineLguest")) == 0)
 			return (long)p + strlen("GenuineLguest") + page_offset;
 
-	err(1, "Is this image a genuine lguest?");
+	errx(1, "Is this image a genuine lguest?");
 }
 
 /* This routine takes an open vmlinux image, which is in ELF, and maps it into
@@ -858,7 +858,7 @@ static u32 handle_block_output(int fd, const struct iovec *iov,
 	/* We first check that the read or write is within the length of the
 	 * block file. */
 	if (off >= device_len)
-		err(1, "Bad offset %llu vs %llu", off, device_len);
+		errx(1, "Bad offset %llu vs %llu", off, device_len);
 	/* Move to the right location in the block file.  This shouldn't fail,
 	 * but best to check. */
 	if (lseek64(dev->fd, off, SEEK_SET) != off)