generic: handle baremetal dependencies
generic: handle baremetal dependencies

cmake check_include_files() tries to build an executable by default,
this works for linux when it is both host and target.
Building libmetal for baremetal with no tests/examples shall not require libxil.a

Signed-off-by: Sam Sortais <d25874581fb37a0b69e80e1fc7fefdee73c62174@xilinx.com>

forg0ne/libmetal,forg0ne/libmetal