gmacros: Only set G_ANALYZER_ANALYZING to 1 when clang static analyzer is in use
gmacros: Only set G_ANALYZER_ANALYZING to 1 when clang static analyzer is in use

We set G_ANALYZER_ANALYZING to 1 when clang supporting static analyzing before,
but this will cause compilation error when -Werror=return-type is used and the
static analyzer is not in use because g_error static function only has
__attribute__((analyzer_noreturn)), which is useless for normal compilation.

https://bugzilla.gnome.org/show_bug.cgi?id=741901

tamaskenez/glib,MathieuDuponchelle/glib,MathieuDuponchelle/glib,MathieuDuponchelle/glib,johne53/MB3Glib,Distrotech/glib,krichter722/glib,ieei/glib,johne53/MB3Glib,tamaskenez/glib,tchakabam/glib,gale320/glib,cention-sany/glib,cention-sany/glib,cention-sany/glib,gale320/glib,gale320/glib,Distrotech/glib,endlessm/glib,cention-sany/glib,johne53/MB3Glib,johne53/MB3Glib,mzabaluev/glib,tamaskenez/glib,Distrotech/glib,Distrotech/glib,cention-sany/glib,endlessm/glib,tamaskenez/glib,endlessm/glib,ieei/glib,mzabaluev/glib,MathieuDuponchelle/glib,johne53/MB3Glib,tamaskenez/glib,endlessm/glib,ieei/glib,tchakabam/glib,krichter722/glib,MathieuDuponchelle/glib,gale320/glib,tchakabam/glib,tchakabam/glib,Distrotech/glib,krichter722/glib,johne53/MB3Glib,mzabaluev/glib,endlessm/glib,ieei/glib,tchakabam/glib,ieei/glib,krichter722/glib,krichter722/glib,gale320/glib,mzabaluev/glib,mzabaluev/glib