libpcap: apply fix from upstream to fix build race

../libpcap-1.8.1/grammar.y:78:10:
fatal error: scanner.h: No such file or directory

(From OE-Core rev: aaed4e92d79919e40c896536fcb4ff6567c9a755)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-connectivity/libpcap/libpcap/fix-grammar-deps.patch

@@ -0,0 +1,29 @@
+Fix a missing dependency that can result in:
+
+../libpcap-1.8.1/grammar.y:78:10: fatal error: scanner.h: No such file or directory
+
+Upstream-Status: Backport
+Signed-off-by: Ross Burton <ross.burton@intel.com>
+
+From 0dd90a6bdbce4dca14106859eee63ef643a106e2 Mon Sep 17 00:00:00 2001
+From: Alfredo Alvarez Fernandez <alfredoalvarezernandez@gmail.com>
+Date: Tue, 21 Feb 2017 11:41:43 +0100
+Subject: [PATCH] Makefile.in: Fix missing dependency
+
+---
+ Makefile.in | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/Makefile.in b/Makefile.in
+index 7044f043..f5d443ae 100644
+--- a/Makefile.in
++++ b/Makefile.in
+@@ -465,7 +465,7 @@ grammar.h: grammar.c
+ 		$(MAKE) $(MAKEFLAGS) grammar.c; \
+ 	fi
+ 
+-grammar.o: grammar.c
++grammar.o: grammar.c scanner.h
+ 	$(CC) $(FULL_CFLAGS) -c grammar.c
+ 
+ gencode.o: $(srcdir)/gencode.c grammar.h scanner.h

meta/recipes-connectivity/libpcap/libpcap_1.8.1.bb

@@ -5,6 +5,7 @@ SRC_URI += " \
     file://0001-Fix-compiler_state_t.ai-usage-when-INET6-is-not-defi.patch \
     file://0002-Add-missing-compiler_state_t-parameter.patch \
     file://disable-remote.patch \
+    file://fix-grammar-deps.patch \
 "
 
 SRC_URI[md5sum] = "3d48f9cd171ff12b0efd9134b52f1447"