all: Format code to add space after C++-style comment start.

Note: the uncrustify configuration is explicitly set to 'add' instead of
'force' in order not to alter the comments which use extra spaces after //
as a means of indenting text for clarity.
diff --git a/py/emitbc.c b/py/emitbc.c
index e90c28c..c74b7fb 100644
--- a/py/emitbc.c
+++ b/py/emitbc.c
@@ -940,4 +940,4 @@
 };
 #endif
 
-#endif //MICROPY_ENABLE_COMPILER
+#endif // MICROPY_ENABLE_COMPILER