linux_riscv: Move patches to my Linux fork.

All patches there are also submitted upstream and will be removed if
rejected.

Also includes some fixes to get module loading working.

pkgs/os-specific/linux/kernel/patches.nix

@@ -73,33 +73,4 @@ rec {
     };
   };
 
-  riscv_modules = {
-    name = "riscv-modules";
-    patch = ./riscv-modules.patch;
-  };
-
-  # http://lists.infradead.org/pipermail/linux-riscv/2018-February/000054.html
-  riscv_irq_busy = {
-    name = "riscv-irq-busy";
-    patch = ./riscv-irq-busy.patch;
-  };
-
-  # http://lists.infradead.org/pipermail/linux-riscv/2018-February/000059.html
-  riscv_install = {
-    name = "riscv-install";
-    patch = ./riscv-install.patch;
-  };
-
-  # http://lists.infradead.org/pipermail/linux-riscv/2018-February/000056.html
-  riscv_initrd = {
-    name = "riscv-initrd";
-    patch = ./riscv-initrd.patch;
-  };
-
-  # http://lists.infradead.org/pipermail/linux-riscv/2018-February/000058.html
-  riscv_initrd_free = {
-    name = "riscv-initrd-free";
-    patch = ./riscv-initrd-free.patch;
-  };
-
 }