fix(risc): remove repetition

Author: elge@alpha15

bare-metal/elastic-metal/reference-content/elastic-metal-rv1-guidelines.mdx

@@ -71,7 +71,7 @@ Linux kernel.
     ```bash
     cd linux/
 
-    # Make sure the device required device tree is available in the default branch
+    # Make sure the required device tree is available in the default branch
     ls -lhF arch/riscv/boot/dts/thead/th1520-lichee-cluster-4a-16g.dts
     # Otherwise switch to another branch that has it
     #git branch -a