libdc1394: disable building examples

Building the examples suffers from host contamination and therefore does not
succeed.

	| arm-oe-linux-gnueabi-libtool: link: arm-oe-linux-gnueabi-gcc -march=armv5te
		-marm -mthumb-interwork --sysroot=...
		-I/usr/include/SDL ...
		-lrt -L/usr/lib64 ...
	| /SSD/build/distroless/tmp/qemuarm-eglibc/sysroots/x86_64-linux/usr/libexec/armv5te-oe-linux-gnueabi/gcc/arm-oe-linux-gnueabi/4.8.2/ld:
		warning: library search path "/usr/lib64" is unsafe for cross-compilation
	| /usr/lib64/librt.so: file not recognized: File format not recognized

Signed-off-by: Trevor Woerner <trevor.woerner@linaro.org>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>