all: format code according to Go 1.19 rules

Go 1.19 started reformatting code in a way that makes it more obvious
how it will be rendered on pkg.go.dev. It gets it almost right, but not
entirely. Therefore, I had to modify some of the comments so that they
are formatted correctly.

src/runtime/runtime_esp32.go

@@ -11,6 +11,7 @@ import (
 
 // This is the function called on startup right after the stack pointer has been
 // set.
+//
 //export main
 func main() {
 	// Disable the protection on the watchdog timer (needed when started from