tests: All update tests should use unique temporary file names and cleanup.

All update tests used the same temporary file name xxx. And only update4
would clean up this file. Now that tests can run in parallel make sure
all temporary names are unique and every test cleans up their own files.

Signed-off-by: Mark Wielaard <mjw@redhat.com>
diff --git a/tests/update3.c b/tests/update3.c
index 1a62b34..d760687 100644
--- a/tests/update3.c
+++ b/tests/update3.c
@@ -26,6 +26,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
 #include ELFUTILS_HEADER(ebl)
 
@@ -33,7 +34,7 @@
 int
 main (int argc, char *argv[] __attribute__ ((unused)))
 {
-  const char *fname = "xxx";
+  const char *fname = "xxx_update3";
   int fd;
   Elf *elf;
   Elf32_Ehdr *ehdr;
@@ -198,5 +199,7 @@
       exit (1);
     }
 
+  unlink (fname);
+
   return 0;
 }