package/libfreeglut: fix build with gcc 10

Fixes:
 - http://autobuild.buildroot.org/results/48c11cfc19784cc9c3ba5c6ba3d91ddae192734e

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libfreeglut/0001-Work-around-for-an-issue-which-cropped-up-with-the-release-of-gcc-10.patch

@@ -0,0 +1,69 @@
+From b9998bbc1e1c329f6bf69c24606a2be7a4973b8c Mon Sep 17 00:00:00 2001
+From: jtsiomb <jtsiomb@7f0cb862-5218-0410-a997-914c9d46530a>
+Date: Fri, 21 Feb 2020 22:25:31 +0000
+Subject: [PATCH] Work-around for an issue which cropped up with the release of
+ gcc-10. In their infinite wisdom, they decided to build with -fno-common as
+ default from now on, breaking every piece of C code which used to declare
+ common symbols in header files, as was the convention since the dawn of time.
+ We now have to duplicate all declarations to an arbitrary source file, and
+ change the header-file ones to prefix them with extern.
+
+git-svn-id: https://svn.code.sf.net/p/freeglut/code/trunk@1863 7f0cb862-5218-0410-a997-914c9d46530a
+[Retrieved from:
+https://github.com/dcnieho/FreeGLUT/commit/b9998bbc1e1c329f6bf69c24606a2be7a4973b8c]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+---
+ freeglut/freeglut/src/fg_gl2.c | 14 ++++++++++++++
+ freeglut/freeglut/src/fg_gl2.h | 14 +++++++-------
+ 2 files changed, 21 insertions(+), 7 deletions(-)
+
+diff --git a/src/fg_gl2.c b/src/fg_gl2.c
+index 38b0acbb..54b4285b 100644
+--- a/src/fg_gl2.c
++++ b/src/fg_gl2.c
+@@ -27,6 +27,20 @@
+ #include "fg_internal.h"
+ #include "fg_gl2.h"
+ 
++#ifndef GL_ES_VERSION_2_0
++/* GLES2 has the corresponding entry points built-in, and these fgh-prefixed
++ * names are defined in fg_gl2.h header to reference them, for any other case,
++ * define them as function pointers here.
++ */
++FGH_PFNGLGENBUFFERSPROC fghGenBuffers;
++FGH_PFNGLDELETEBUFFERSPROC fghDeleteBuffers;
++FGH_PFNGLBINDBUFFERPROC fghBindBuffer;
++FGH_PFNGLBUFFERDATAPROC fghBufferData;
++FGH_PFNGLENABLEVERTEXATTRIBARRAYPROC fghEnableVertexAttribArray;
++FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC fghDisableVertexAttribArray;
++FGH_PFNGLVERTEXATTRIBPOINTERPROC fghVertexAttribPointer;
++#endif
++
+ void FGAPIENTRY glutSetVertexAttribCoord3(GLint attrib) {
+   if (fgStructure.CurrentWindow != NULL)
+     fgStructure.CurrentWindow->Window.attribute_v_coord = attrib;
+diff --git a/src/fg_gl2.h b/src/fg_gl2.h
+index ab8ba5c7..fb3d4676 100644
+--- a/src/fg_gl2.h
++++ b/src/fg_gl2.h
+@@ -67,13 +67,13 @@ typedef void (APIENTRY *FGH_PFNGLENABLEVERTEXATTRIBARRAYPROC) (GLuint index);
+ typedef void (APIENTRY *FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC) (GLuint);
+ typedef void (APIENTRY *FGH_PFNGLVERTEXATTRIBPOINTERPROC) (GLuint index, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const GLvoid *pointer);
+ 
+-FGH_PFNGLGENBUFFERSPROC fghGenBuffers;
+-FGH_PFNGLDELETEBUFFERSPROC fghDeleteBuffers;
+-FGH_PFNGLBINDBUFFERPROC fghBindBuffer;
+-FGH_PFNGLBUFFERDATAPROC fghBufferData;
+-FGH_PFNGLENABLEVERTEXATTRIBARRAYPROC fghEnableVertexAttribArray;
+-FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC fghDisableVertexAttribArray;
+-FGH_PFNGLVERTEXATTRIBPOINTERPROC fghVertexAttribPointer;
++extern FGH_PFNGLGENBUFFERSPROC fghGenBuffers;
++extern FGH_PFNGLDELETEBUFFERSPROC fghDeleteBuffers;
++extern FGH_PFNGLBINDBUFFERPROC fghBindBuffer;
++extern FGH_PFNGLBUFFERDATAPROC fghBufferData;
++extern FGH_PFNGLENABLEVERTEXATTRIBARRAYPROC fghEnableVertexAttribArray;
++extern FGH_PFNGLDISABLEVERTEXATTRIBARRAYPROC fghDisableVertexAttribArray;
++extern FGH_PFNGLVERTEXATTRIBPOINTERPROC fghVertexAttribPointer;
+ 
+ #    endif
+