Adapt external/epm/asan.patch.0 to pre-C99

...as e.g. still used in
<https://ci.libreoffice.org/job/lo_daily_update_gandalf/511/>

Change-Id: I11d85ff9ae7462a4149272344e0b0f52eb120c22

external/epm/asan.patch.0

 --- dist.c
 +++ dist.c
-@@ -405,7 +405,11 @@
+@@ -405,7 +405,12 @@
    for (temp = platform->machine; *temp != '\0'; temp ++)
      if (*temp == '-' || *temp == '_')
      {
 -      strcpy(temp, temp + 1);
-+      for (char * t2 = temp;; ++t2) {
++      char * t2 = temp;
++      for (;; ++t2) {
 +        char c = t2[1];
 +        t2[0] = c;
 +        if (c == '\0') break;