meson: fix build files size explosion

wayland protocols accidently added generated c source files to the
sources. This lead to every dependency of evas compiling those 5 c
source code files again and again and again. Which is completly wrong.
This commit splits up between headers and c files. which reduces the
build files from over 4K to roughly 3K.

Differential Revision: https://phab.enlightenment.org/D7159

src/wayland_protocol/meson.build

@@ -23,31 +23,32 @@ wl_stable_protocol_sys = [
 ]
 
 foreach sys_protocol : wl_unstable_protocol_sys
-	wl_protocol_local += [ 
+	wl_protocol_local += [
 		join_paths(_wayland_protocols.get_pkgconfig_variable('pkgdatadir'), 'unstable',
 			sys_protocol)]
 endforeach
 
 foreach sys_protocol : wl_stable_protocol_sys
-  wl_protocol_local += [ 
+  wl_protocol_local += [
     join_paths(_wayland_protocols.get_pkgconfig_variable('pkgdatadir'), 'stable',
       sys_protocol)]
 endforeach
 
-gen_obj = []
+gen_obj_c = []
+gen_obj_header = []
 
 foreach item : wl_protocol_local
-  gen_obj += custom_target('wl_code_'+item.underscorify(),
+  gen_obj_c += custom_target('wl_code_'+item.underscorify(),
     input: item,
     output : ['@BASENAME@-protocol.c'],
     command: [wayland_scanner_bin, ['code','@INPUT@','@OUTPUT@']]
   )
-  gen_obj += custom_target('wl_client_header_'+item.underscorify(),
+  gen_obj_header += custom_target('wl_client_header_'+item.underscorify(),
     input: item,
     output : ['@BASENAME@-client-protocol.h'],
     command: [wayland_scanner_bin, ['client-header','@INPUT@','@OUTPUT@']]
   )
-  gen_obj += custom_target('wl_server_header_'+item.underscorify(),
+  gen_obj_header += custom_target('wl_server_header_'+item.underscorify(),
     input: item,
     output : ['@BASENAME@-server-protocol.h'],
     command: [wayland_scanner_bin, ['server-header','@INPUT@','@OUTPUT@']]
@@ -56,12 +57,12 @@ endforeach
 
 
 wayland_protocol_lib = static_library('wayland_protocol',
-    gen_obj,
+    gen_obj_c + gen_obj_header,
 )
 
 wayland_protocol = declare_dependency(
 	include_directories: include_directories('.'),
 	link_with: wayland_protocol_lib,
-  sources: gen_obj,
+  sources: gen_obj_header,
   dependencies : [wayland_client]
-)
+)