mpy-cross, unix, windows, stmhal: Enable return-if-else optimisation.

Prior to making this a config option it was previously available on these
(and all other) ports, and it makes sense to keep it enabled for mpy-cross
as well as ports that have a decent amount of space for the code.

mpy-cross/mpconfigport.h

@@ -44,6 +44,7 @@
 #define MICROPY_COMP_CONST          (1)
 #define MICROPY_COMP_DOUBLE_TUPLE_ASSIGN (1)
 #define MICROPY_COMP_TRIPLE_TUPLE_ASSIGN (1)
+#define MICROPY_COMP_RETURN_IF_EXPR (1)
 
 #define MICROPY_OPT_CACHE_MAP_LOOKUP_IN_BYTECODE (0)
 

stmhal/mpconfigport.h

@@ -45,6 +45,7 @@
 // compiler configuration
 #define MICROPY_COMP_MODULE_CONST   (1)
 #define MICROPY_COMP_TRIPLE_TUPLE_ASSIGN (1)
+#define MICROPY_COMP_RETURN_IF_EXPR (1)
 
 // optimisations
 #define MICROPY_OPT_COMPUTED_GOTO   (1)

unix/mpconfigport.h

@@ -45,6 +45,7 @@
 #endif
 #define MICROPY_COMP_MODULE_CONST   (1)
 #define MICROPY_COMP_TRIPLE_TUPLE_ASSIGN (1)
+#define MICROPY_COMP_RETURN_IF_EXPR (1)
 #define MICROPY_ENABLE_GC           (1)
 #define MICROPY_ENABLE_FINALISER    (1)
 #define MICROPY_STACK_CHECK         (1)

windows/mpconfigport.h

@@ -38,6 +38,7 @@
 #define MICROPY_EMIT_INLINE_THUMB   (0)
 #define MICROPY_COMP_MODULE_CONST   (1)
 #define MICROPY_COMP_TRIPLE_TUPLE_ASSIGN (1)
+#define MICROPY_COMP_RETURN_IF_EXPR (1)
 #define MICROPY_ENABLE_GC           (1)
 #define MICROPY_ENABLE_FINALISER    (1)
 #define MICROPY_STACK_CHECK         (1)