file.c: move chdir parser to a separate file

* chdir.c: New file.
* Makefile.am (strace_SOURCES): Add it.
* file.c (sys_chdir): Move to chdir.c.

Makefile.am

@@ -22,6 +22,7 @@ strace_SOURCES =	\
 	block.c		\
 	cacheflush.c	\
 	capability.c	\
+	chdir.c		\
 	chmod.c		\
 	chown.c		\
 	count.c		\

chdir.c

@@ -0,0 +1,10 @@
+#include "defs.h"
+
+int
+sys_chdir(struct tcb *tcp)
+{
+	if (entering(tcp)) {
+		printpath(tcp, tcp->u_arg[0]);
+	}
+	return 0;
+}

file.c

@@ -1241,13 +1241,3 @@ sys_lxstat(struct tcb *tcp)
 }
 
 #endif /* SPARC[64] */
-
-/* directory */
-int
-sys_chdir(struct tcb *tcp)
-{
-	if (entering(tcp)) {
-		printpath(tcp, tcp->u_arg[0]);
-	}
-	return 0;
-}