Rename PRIVATE to PPRIVATE in order to avoid a name clash resulting in errors like this:
    putty-0.75/cmdgen.c:228:12: error: expected identifier before numeric constant
        enum { PRIVATE, PUBLIC, PUBLICO, FP, OPENSSH_AUTO,

--- putty-0.78/cmdgen.c.orig	2022-10-28 19:19:44.000000000 +0000
+++ putty-0.78/cmdgen.c	2022-11-02 21:26:32.194021545 +0000
@@ -240,8 +240,8 @@
     BinarySource *infile_bs = NULL;
     enum { NOKEYGEN, RSA1, RSA2, DSA, ECDSA, EDDSA } keytype = NOKEYGEN;
     char *outfile = NULL, *outfiletmp = NULL;
-    enum { PRIVATE, PUBLIC, PUBLICO, FP, OPENSSH_AUTO,
-           OPENSSH_NEW, SSHCOM, TEXT, CERTINFO } outtype = PRIVATE;
+    enum { PPRIVATE, PUBLIC, PUBLICO, FP, OPENSSH_AUTO,
+           OPENSSH_NEW, SSHCOM, TEXT, CERTINFO } outtype = PPRIVATE;
     int bits = -1;
     const char *comment = NULL;
     char *origcomment = NULL;
@@ -591,7 +591,7 @@
                         else if (!strcmp(p, "public-openssh"))
                             outtype = PUBLICO;
                         else if (!strcmp(p, "private"))
-                            outtype = PRIVATE;
+                            outtype = PPRIVATE;
                         else if (!strcmp(p, "fingerprint"))
                             outtype = FP;
                         else if (!strcmp(p, "private-openssh"))
@@ -742,7 +742,7 @@
      * We must save the private part when generating a new key.
      */
     if (keytype != NOKEYGEN &&
-        (outtype != PRIVATE && outtype != OPENSSH_AUTO &&
+        (outtype != PPRIVATE && outtype != OPENSSH_AUTO &&
          outtype != OPENSSH_NEW && outtype != SSHCOM && outtype != TEXT)) {
         fprintf(stderr, "puttygen: this would generate a new key but "
                 "discard the private part\n");
@@ -819,8 +819,8 @@
      * Also in this code, we bomb out if the input and output file
      * formats are the same and no other action is performed.
      */
-    if ((intype == SSH_KEYTYPE_SSH1 && outtype == PRIVATE) ||
-        (intype == SSH_KEYTYPE_SSH2 && outtype == PRIVATE) ||
+    if ((intype == SSH_KEYTYPE_SSH1 && outtype == PPRIVATE) ||
+        (intype == SSH_KEYTYPE_SSH2 && outtype == PPRIVATE) ||
         (intype == SSH_KEYTYPE_OPENSSH_PEM && outtype == OPENSSH_AUTO) ||
         (intype == SSH_KEYTYPE_OPENSSH_NEW && outtype == OPENSSH_NEW) ||
         (intype == SSH_KEYTYPE_SSHCOM && outtype == SSHCOM)) {
@@ -841,7 +841,7 @@
              * Bomb out rather than automatically choosing to write
              * a private key file to stdout.
              */
-            if (outtype == PRIVATE || outtype == OPENSSH_AUTO ||
+            if (outtype == PPRIVATE || outtype == OPENSSH_AUTO ||
                 outtype == OPENSSH_NEW || outtype == SSHCOM) {
                 fprintf(stderr, "puttygen: need to specify an output file\n");
                 RETURN(1);
@@ -866,7 +866,7 @@
           intype == SSH_KEYTYPE_SSH2_PUBLIC_RFC4716 ||
           intype == SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH);
     bool outtype_has_private =
-        outtype == PRIVATE || outtype == OPENSSH_AUTO ||
+        outtype == PPRIVATE || outtype == OPENSSH_AUTO ||
         outtype == OPENSSH_NEW || outtype == SSHCOM;
     if (outtype_has_private || intype_entirely_encrypted ||
         (outtype == TEXT && intype_has_private))
@@ -1314,7 +1314,7 @@
         bool ret;
         int real_outtype;
 
-      case PRIVATE:
+      case PPRIVATE:
         random_ref(); /* we'll need a few random bytes in the save file */
         if (sshver == 1) {
             assert(ssh1key);