file.c: move utime parser to a separate file

* utime.c: New file.
* Makefile.am (strace_SOURCES): Add it.
* file.c (sys_utime): Move to utime.c.
diff --git a/Makefile.am b/Makefile.am
index 0516344..ae535d4 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -72,6 +72,7 @@
 	time.c		\
 	umount.c	\
 	util.c		\
+	utime.c		\
 	v4l2.c		\
 	vsprintf.c	\
 	xattr.c