riscv: Remove common.h usage

We can remove common.h from most cases of the code here, and only a few
places need an additional header instead.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Rick Chen <rick@andestech.com>

arch/riscv/lib/sbi.c

@@ -7,7 +7,7 @@
  * Taken from Linux arch/riscv/kernel/sbi.c
  */
 
-#include <common.h>
+#include <errno.h>
 #include <asm/encoding.h>
 #include <asm/sbi.h>