Build against the system's HIDAPI instead of the bundled one.

--- open-zwave-1.6-checkout/cpp/build/support.mk	2019-06-16 15:15:34.258331628 +0200
+++ open-zwave-1.6-checkout/cpp/build/support.mk	2019-06-16 15:15:54.698249462 +0200
@@ -86,6 +86,10 @@ endif
 endif
 SED    := sed
 
+# Build against the system's HIDAPI.
+CPPFLAGS += $(shell pkg-config hidapi-libusb --cflags)
+LDFLAGS  += $(shell pkg-config hidapi-libusb --libs)
+
 #determine if we are release or debug Build and set appropriate flags
 ifeq ($(BUILD), release)
 CFLAGS	+= -c $(RELEASE_CFLAGS)
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