REGTEST: Exclude freebsd target for some reg tests.

This patch excludes freebsd target for health-checks reg tests
which rely on TCP_DEFER_ACCEPT usage. This is specific to Linux.

reg-tests/checks/s00000.vtc

@@ -2,6 +2,7 @@ varnishtest "Health-check test"
 feature ignore_unknown_macro
 
 #REQUIRE_VERSION=1.8
+#EXCLUDE_TARGETS=freebsd
 
 # This script test health-checks for four backends with one server by backend.
 # A syslog server is attached to each backend to check the syslog messages

reg-tests/checks/s00001.vtc

@@ -6,6 +6,8 @@ feature ignore_unknown_macro
 # The first health-checks passed tests are checked for all these servers
 # thanks to syslog messages.
 
+#EXCLUDE_TARGETS=freebsd
+
 # Note that the first syslog message received is: "Proxy <name> started."
 syslog S -repeat 21 -level notice {
     recv

reg-tests/checks/s00002.vtc

@@ -2,6 +2,7 @@ varnishtest "Health-checks"
 feature ignore_unknown_macro
 
 #REQUIRE_VERSION=1.8
+#EXCLUDE_TARGETS=freebsd
 
 # This script start 40 servers named s0 up to s39.
 # For 0 <= i <= 19: