build: Install .pc files in correct location

If a library is provided in the positional arguments, then meson
defaults to installing the .pc file in a 'pkgconfig' subdirectory
in the library's install location. We want the files in the regular
$libdir/pkgconfig rather than $libdir/mutter-$api/pkgconfig, so
specify the location explicitly in the parameters.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/382

clutter/clutter/meson.build

@@ -634,6 +634,7 @@ pkg.generate(libmutter_clutter,
   variables: [
     'apiversion=' + libmutter_api_version,
   ],
+  install_dir: pcdir,
 )
 
 pkg.generate(libmutter_clutter,
@@ -647,4 +648,5 @@ pkg.generate(libmutter_clutter,
   variables: [
     'apiversion=' + libmutter_api_version,
   ],
+  install_dir: pcdir,
 )

cogl/cogl-gles2/meson.build

@@ -37,4 +37,5 @@ pkg.generate(libmutter_cogl_gles2,
   variables: [
     'apiversion=' + libmutter_api_version,
   ],
+  install_dir: pcdir,
 )

cogl/cogl-pango/meson.build

@@ -77,4 +77,5 @@ pkg.generate(libmutter_cogl_pango,
   variables: [
     'apiversion=' + libmutter_api_version,
   ],
+  install_dir: pcdir,
 )

cogl/cogl-path/meson.build

@@ -78,4 +78,5 @@ pkg.generate(libmutter_cogl_path,
   variables: [
     'apiversion=' + libmutter_api_version,
   ],
+  install_dir: pcdir,
 )

cogl/cogl/meson.build

@@ -528,4 +528,5 @@ pkg.generate(libmutter_cogl,
   variables: [
     'apiversion=' + libmutter_api_version,
   ],
+  install_dir: pcdir,
 )

meson.build

@@ -65,6 +65,8 @@ pkgdatadir = join_paths(datadir, pkgname)
 pkglibdir = join_paths(libdir, pkgname)
 pkgincludedir = join_paths(includedir, pkgname)
 
+pcdir = join_paths(libdir, 'pkgconfig')
+
 gettext_package = meson.project_name()
 localedir = join_paths(datadir, 'locale')
 

src/meson.build

@@ -841,6 +841,7 @@ pkg.generate(libmutter,
     'girdir=${libdir}/mutter-' + libmutter_api_version,
     'typelibdir=${libdir}/mutter-' + libmutter_api_version,
   ],
+  install_dir: pcdir,
 )
 
 subdir('compositor/plugins')