Configurations/10-main.conf: update iOS commentary.

Reviewed-by: NRichard Levitte <levitte@openssl.org>

Configurations/10-main.conf

@@ -1388,7 +1388,7 @@
         inherit_from     => [ "darwin-common", asm("armv4_asm") ],
         # It should be possible to go below iOS 6 and even add -arch armv6,
         # thus targeting iPhone pre-3GS, but it's assumed to be irrelevant
-        # at this point (and impossible to download SDK for).
+        # at this point.
         cflags           => "-arch armv7 -mios-version-min=6.0.0 -isysroot \$(CROSS_TOP)/SDKs/\$(CROSS_SDK) -fno-common",
         sys_id           => "iOS",
         perlasm_scheme   => "ios32",