build: exclude meson files from examples installation

build: exclude meson files from examples installation

The meson.build files in each example directory is simply to support
building the example as part of the main SDK build, and these should not
be installed with the example's source code and makefile. The exclude of
"meson.build" only filters out the top-level examples/meson.build file,
not the file in each subdirectory.

To fix this, we can build up the list of files to exclude based off the
list of all examples. With this change "find examples/ -name meson.build"
returns no hits when run on an installed instance.

Fixes: e5b95003f1df ("examples: fix flattening directory layout on install")
Cc: stable@dpdk.org
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>