RISC-V: Moved syscalls to separate files to fix aliasing problems.

libgloss/riscv/sys_getpid.c

@@ -0,0 +1,11 @@
+#include <machine/syscall.h>
+
+/* Get process id. This is sometimes used to generate strings unlikely
+   to conflict with other processes. Minimal implementation for a
+   system without processes just returns 1.  */
+
+int
+_getpid()
+{
+  return 1;
+}