libfpx: pull upstream fix for -fno-common toolchains
libfpx: pull upstream fix for -fno-common toolchains

Without the change build fails on upstream gcc-10 as:

    ld: ri_image/.libs/libRiImage.a(cp_jpeg.o):/build/libfpx-1.3.1-7/ri_image/../jpeg/ejpeg.h:35:
      multiple definition of `No_JPEG_Header_Flag'; jpeg/.libs/libJpeg.a(enctile.o):/build/libfpx-1.3.1-7/jpeg/ejpeg.h:35: first defined here

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs