[cogl-debug] avoid warnings when using COGL_NOTE with unbraced else clauses
[cogl-debug] avoid warnings when using COGL_NOTE with unbraced else clauses

When not building a debug build the compiler was warning about empty
else clauses with no braces due to code like:
  if (blah)
	do_foo();
  else
	COGL_NOTE (DRAW, "a-wibble");

This simply ensures that even for non debug builds COGL_NOTE will expand to
a single statement.

Distrotech/cogl,spatulasnout/cogl,spatulasnout/cogl,collects/cogl,djdeath/cogl,gcampax/cogl,gcampax/cogl,djdeath/cogl-android,djdeath/cogl,djdeath/cogl-android,djdeath/cogl,djdeath/cogl-android,Distrotech/cogl,Distrotech/cogl,Distrotech/cogl,gcampax/cogl,gcampax/cogl,collects/cogl