man: pc.5: document copyright/maintainer fields

man/pc.5

@@ -99,6 +99,9 @@ These flags are always used, regardless of whether static compilation is request
 .It Cflags.private
 Required compiler flags for static compilation.
 (optional; fragment list; pkgconf extension)
+.It Copyright
+A copyright attestation statement.
+(optional; literal; pkgconf extension)
 .It Libs
 Required linking flags for this package.
 Libraries this package depends on for linking against it, which are not
@@ -113,6 +116,10 @@ not described as dependencies should be specified here.
 .It License
 The asserted SPDX license tag that should be applied to the given package.
 (optional; literal; pkgconf extension)
+.It Maintainer
+The preferred contact for the maintainer.  This should be in the format of a
+name followed by an e-mail address or website.
+(optional; literal; pkgconf extension)
 .It Requires
 Required dependencies that must be met for the package to be usable.
 All dependencies must be satisfied or the pkg-config implementation must not use
@@ -154,6 +161,9 @@ includedir=${prefix}/include
 
 Name: libfoo                                  # human-readable name
 Description: an example library called libfoo # human-readable description
+Copyright: Copyright (c) 2022 pkgconf project authors
+License: Apache-2.0
+Maintainer: the pkgconf project <http://www.pkgconf.org>
 Version: 1.0
 URL: http://www.pkgconf.org
 Requires: libbar > 2.0.0