os2: make platform error more ergonomic by making it an alias

core/os/os2/errors.odin

@@ -30,7 +30,7 @@ General_Error :: enum u32 {
 	Unsupported,
 }
 
-Platform_Error :: enum i32 {None=0}
+Platform_Error :: _Platform_Error
 
 Error :: union #shared_nil {
 	General_Error,

core/os/os2/errors_linux.odin

@@ -3,6 +3,8 @@ package os2
 
 import "core:sys/linux"
 
+_Platform_Error :: linux.Errno
+
 @(rodata)
 _errno_strings := [linux.Errno]string{
 	.NONE            = "",

core/os/os2/errors_posix.odin

@@ -4,6 +4,8 @@ package os2
 
 import "core:sys/posix"
 
+_Platform_Error :: posix.Errno
+
 _error_string :: proc(errno: i32) -> string {
 	return string(posix.strerror(posix.Errno(errno)))
 }

core/os/os2/errors_windows.odin

@@ -5,6 +5,8 @@ import "base:runtime"
 import "core:slice"
 import win32 "core:sys/windows"
 
+_Platform_Error :: win32.System_Error
+
 _error_string :: proc(errno: i32) -> string {
 	e := win32.DWORD(errno)
 	if e == 0 {