bpo-35550: Fix incorrect Solaris define guards (GH-11275)


Python source code uses on several places ifdef sun or defined(sun) without the underscores, which is not standard compliant and shouldn't be used.

Defines should check for __sun instead. Reference: http://nadeausoftware.com/articles/2012/01/c_c_tip_how_use_compiler_predefined_macros_detect_operating_systemGH-Solaris

https://bugs.python.org/issue35550
(cherry picked from commit 6f9bc72c79c3262e5d0f2c0e96b016477399cfb1)

Co-authored-by: Jakub KulĂ­k <Kulikjak@gmail.com>
diff --git a/Modules/timemodule.c b/Modules/timemodule.c
index 5e99bd8..bbfb7db 100644
--- a/Modules/timemodule.c
+++ b/Modules/timemodule.c
@@ -725,7 +725,7 @@
         return NULL;
     }
 
-#if defined(_MSC_VER) || defined(sun) || defined(_AIX)
+#if defined(_MSC_VER) || (defined(__sun) && defined(__SVR4)) || defined(_AIX)
     if (buf.tm_year + 1900 < 1 || 9999 < buf.tm_year + 1900) {
         PyErr_SetString(PyExc_ValueError,
                         "strftime() requires year in [1; 9999]");
@@ -771,7 +771,7 @@
             return NULL;
         }
     }
-#elif (defined(_AIX) || defined(sun)) && defined(HAVE_WCSFTIME)
+#elif (defined(_AIX) || (defined(__sun) && defined(__SVR4))) && defined(HAVE_WCSFTIME)
     for (outbuf = wcschr(fmt, '%');
         outbuf != NULL;
         outbuf = wcschr(outbuf+2, '%'))