ios: move `sokol` declarations out of builder, and support non-sokol apps too (#9703)

vlib/sokol/c/declaration.c.v

@@ -12,8 +12,14 @@ pub const (
 #flag freebsd -L/usr/local/lib -lX11 -lGL -lXcursor -lXi
 #flag windows -lgdi32
 // METAL
-#flag darwin -DSOKOL_METAL
+$if darwin {
-#flag darwin -framework Metal -framework Cocoa -framework MetalKit -framework QuartzCore
+	#flag -DSOKOL_METAL
+	#flag -framework Metal -framework Cocoa -framework MetalKit -framework QuartzCore
+}
+$if ios {
+	#flag -DSOKOL_METAL
+	#flag -framework Foundation -framework Metal -framework MetalKit -framework UIKit
+}
 // OPENGL
 #flag linux -DSOKOL_GLCORE33
 #flag freebsd -DSOKOL_GLCORE33

vlib/v/builder/cc.v

@@ -202,11 +202,6 @@ fn (mut v Builder) setup_ccompiler_options(ccompiler string) {
 		'-Wno-format-nonliteral',
 	]
 	if v.pref.os == .ios {
-		ccoptions.args << '-framework Foundation'
-		ccoptions.args << '-framework UIKit'
-		ccoptions.args << '-framework Metal'
-		ccoptions.args << '-framework MetalKit'
-		ccoptions.args << '-DSOKOL_METAL'
 		ccoptions.args << '-fobjc-arc'
 	}
 	ccoptions.debug_mode = v.pref.is_debug

vlib/v/gen/c/cmain.v

@@ -12,7 +12,10 @@ pub fn (mut g Gen) gen_c_main() {
 	}
 	g.out.writeln('')
 	main_fn_start_pos := g.out.len
-	if (g.pref.os == .android && g.pref.is_apk) || g.pref.os == .ios {
+
+	is_sokol := 'sokol' in g.table.imports
+
+	if (g.pref.os == .android && g.pref.is_apk) || (g.pref.os == .ios && is_sokol) {
 		g.gen_c_android_sokol_main()
 	} else {
 		g.gen_c_main_header()