Add necessary #include <config.h> directives

src/fl_draw_pixmap.cxx

@@ -30,6 +30,7 @@
 // The above comments were checked in as r2, and much has changed since then;
 // transparency added, color cube not required, etc.      -erco Oct 20 2013
 
+#include <config.h>
 #include <FL/Fl.H>
 #include "Fl_System_Driver.H"
 #include <FL/platform.H>

src/nanosvg.cxx

@@ -34,6 +34,7 @@
 //       Once this is available we can remove this comment block and
 //       the following 3-line "fix":
 
+#include <config.h>
 #include <math.h>                       // must be before #define below !
 static float nsvg__roundf(float x);     // prototype (see nanosvgrast.h)
 #define roundf nsvg__roundf             // redefinition (#937)