Configurations/10-main.conf: amend out-dated comments.

Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5502)

Configurations/10-main.conf

@@ -11,6 +11,7 @@ sub vc_win64a_info {
                                 asflags   => "-Ox -f win64 -DNEAR",
                                 asoutflag => "-o " };
         } elsif ($disabled{asm}) {
+            # assembler is still used to compile uplink shim
             $vc_win64a_info = { AS        => "ml64",
                                 ASFLAGS   => "/Zi",
                                 asflags   => "/c /Cp /Cx",
@@ -38,6 +39,7 @@ sub vc_win32_info {
                                asoutflag => "-o ",
                                perlasm_scheme => "win32n" };
         } elsif ($disabled{asm}) {
+            # not actually used, uplink shim is inlined into C code
             $vc_win32_info = { AS        => "ml",
                                ASFLAGS   => "/nologo /Zi",
                                asflags   => "/Cp /coff /c /Cx",
@@ -1460,8 +1462,10 @@ my %targets = (
         multilib         => "-x64",
     },
     "VC-WIN32" => {
-        # x86 Win32 target defaults to ANSI API, if you want UNICODE,
-        # configure with 'perl Configure VC-WIN32 -DUNICODE -D_UNICODE'
+        # x86 Win32 target used to default to ANSI API, but not anymore,
+        # UNICODE is the only option. The original reason for providing
+        # UNICODE as opt-in option was because ANSI API was *native*
+        # system interface for [no longer supported] Windows 9x.
         inherit_from     => [ "VC-noCE-common", asm("x86_asm"),
                               sub { $disabled{shared} ? () : "uplink_common" } ],
         CFLAGS           => add("-WX"),