[meson] Make it work with Windows.

* meson.build: Do not process `ftconfig.h` when not using
`ftconfig.h.in`.

Fixes #1029.

ChangeLog

@@ -1,3 +1,12 @@
+2021-03-07  Xavier Claessens  <xavier.claessens@collabora.com>
+
+	[meson] Make it work with Windows.
+
+	* meson.build: Do not process `ftconfig.h` when not using
+	`ftconfig.h.in`.
+
+	Fixes #1029.
+
 2021-02-25  Werner Lemberg  <wl@gnu.org>
 
 	[woff2] Fix memory leak.

meson.build

@@ -288,6 +288,7 @@ if host_machine.system() == 'windows'
   ft2_defines += ['-DDLL_EXPORT=1']
 endif
 
+
 # Generate `ftconfig.h`
 
 ftconfig_command = process_header_command
@@ -300,20 +301,17 @@ endif
 
 if host_machine.system() in ['linux', 'darwin', 'cygwin']
   ftconfig_h_in = files('builds/unix/ftconfig.h.in')
-else
-  ftconfig_h_in = files('include/freetype/config/ftconfig.h')
+  ftconfig_h = custom_target('ftconfig.h',
+    input: ftconfig_h_in,
+    output: 'ftconfig.h',
+    command: ftconfig_command,
+    install: true,
+    install_dir: 'include/freetype2/freetype/config',
+  )
+  ft2_sources += ftconfig_h
+  ft2_defines += ['-DFT_CONFIG_CONFIG_H=<ftconfig.h>']
 endif
 
-ftconfig_h = custom_target('ftconfig.h',
-  input: ftconfig_h_in,
-  output: 'ftconfig.h',
-  command: ftconfig_command,
-  install: true,
-  install_dir: 'include/freetype2/freetype/config',
-)
-ft2_sources += ftconfig_h
-ft2_defines += ['-DFT_CONFIG_CONFIG_H=<ftconfig.h>']
-
 
 ft2_lib = library('freetype',
   sources: ft2_sources + [ftmodule_h],