Removed riscv- modules

Author: cesare

.gitmodules

@@ -1,6 +0,0 @@
-[submodule "riscv-gnu-toolchain"]
-	path = riscv-gnu-toolchain
-	url = https://github.com/riscv/riscv-gnu-toolchain.git
-[submodule "riscv-openocd"]
-	path = riscv-openocd
-	url = https://github.com/riscv/riscv-openocd.git