libutils/mipmap.c: Fixed possible memory leak

In case of malloc() failure memory allocated for both 'srcImage'
and 'dstImage' is leaked.

Patch simplified by Brian Paul.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96480
Signed-off-by: Amarnath Valluri <amarnath.valluri@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>

src/libutil/mipmap.c

@@ -4509,6 +4509,8 @@ static int gluBuild2DMipmapLevelsCore(GLenum target, GLint internalFormat,
 	     glPixelStorei(GL_UNPACK_SKIP_PIXELS, psm.unpack_skip_pixels);
 	     glPixelStorei(GL_UNPACK_ROW_LENGTH, psm.unpack_row_length);
 	     glPixelStorei(GL_UNPACK_SWAP_BYTES, psm.unpack_swap_bytes);
+	     free(srcImage);
+	     free(dstImage);
 	     return GLU_OUT_OF_MEMORY;
 	  }