configure: Add require_header() convenience function
authorDiego Biurrun <diego@biurrun.de>
Sun, 22 Jan 2017 15:04:09 +0000 (16:04 +0100)
committerDiego Biurrun <diego@biurrun.de>
Thu, 2 Feb 2017 16:49:51 +0000 (17:49 +0100)
commitaba7fdcc8baaed35e804c7882b70a848a0e566c7
tree12007e490148699cb9f630c37bdc67f1206d96ed
parenta97563c889fefd81ad6b3758471434d8c2e2e550
configure: Add require_header() convenience function

Simplifies checking for external library headers and aborting if
the external library support was requested, but is not available.
configure