vendor: portmidi: simplify foreign import

vendor/portmidi/portmidi.odin

@@ -9,6 +9,8 @@ when ODIN_OS == .Windows {
 		"system:Winmm.lib",
 		"system:Advapi32.lib",
 	}
+} else {
+	foreign import lib "system:portmidi"
 }
 
 #assert(size_of(b32) == size_of(c.int))

vendor/portmidi/util.odin

@@ -7,7 +7,11 @@ package portmidi
 
 import "core:c"
 
-when ODIN_OS == .Windows { foreign import lib "portmidi_s.lib" }
+when ODIN_OS == .Windows {
+	foreign import lib "portmidi_s.lib"
+} else {
+	foreign import lib "system:portmidi"
+}
 
 
 Queue :: distinct rawptr