Code cleanup: Remove const in prototype

Signed-off-by: Jan Kratochvil <jan.kratochvil@redhat.com>
diff --git a/libdwfl/linux-pid-attach.c b/libdwfl/linux-pid-attach.c
index b4f3165..ca82144 100644
--- a/libdwfl/linux-pid-attach.c
+++ b/libdwfl/linux-pid-attach.c
@@ -198,10 +198,8 @@
 /* Implement the ebl_set_initial_registers_tid setfunc callback.  */
 
 static bool
-pid_thread_state_registers_cb (const int firstreg,
-			       unsigned nregs,
-			       const Dwarf_Word *regs,
-			       void *arg)
+pid_thread_state_registers_cb (int firstreg, unsigned nregs,
+			       const Dwarf_Word *regs, void *arg)
 {
   Dwfl_Thread *thread = (Dwfl_Thread *) arg;
   return INTUSE(dwfl_thread_state_registers) (thread, firstreg, nregs, regs);