Kernel compile failure without pci.

[Peter Jeremy]

A kernel including ata but no pci fails during build with an
conflicting declaration of ata_dmastart() in ata-isa.c.  The
fix is below.  Could someone please include this in 4.9 as is
or do I need to file a PR.
============================
RCS file: /usr/ncvs/src/sys/dev/ata/ata-isa.c,v
retrieving revision 1.4.2.2
diff -u -r1.4.2.2 ata-isa.c
--- ata-isa.c   5 Sep 2003 07:29:10 -0000       1.4.2.2
+++ ata-isa.c   21 Sep 2003 09:03:37 -0000
@@ -134,9 +134,10 @@
     return -1;
 }
 
-void
+int
 ata_dmastart(struct ata_device *atadev, caddr_t data, int32_t count, int dir)
 {
+    return -1;
 }
 
 int
============================
Peter