patch 8.1.2084: Amiga: cannot get the user name

Problem:    Amiga: cannot get the user name.
Solution:   Use getpwuid() if available. (Ola Söder, closes #4985)

src/os_amiga.c

@@ -664,7 +664,15 @@ mch_can_restore_icon(void)
     int
 mch_get_user_name(char_u *s, int len)
 {
-    /* TODO: Implement this. */
+#if defined(__amigaos4__) || defined(__AROS__) || defined(__MORPHOS__)
+    struct passwd   *pwd = getpwuid(getuid());
+
+    if (pwd != NULL && pwd->pw_name && len > 0)
+    {
+        vim_strncpy(s, (char_u *)pwd->pw_name, len - 1);
+        return OK;
+    }
+#endif
     *s = NUL;
     return FAIL;
 }

src/os_amiga.h

@@ -90,6 +90,7 @@ typedef long off_t;
 # include <unistd.h>
 # include <limits.h>
 # include <errno.h>
+# include <pwd.h>
 # include <dirent.h>
 #endif
 

src/version.c

@@ -757,6 +757,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2084,
 /**/
     2083,
 /**/