EXP-772 -- Log in failure, keeps saying DNS cannot resolve hostname.

No real progress on this Jira yet but Mac build was not properly reporting the CURL error string.
This check-in fixes that.

So far, I have backed out URL related changes between 2.6.2 and 2.6.3 without any change in behavior.
Unsure how to proceed next although comparing libcares and libcurl builds between 2.6.2 and 2.6.3 seems
like it could be the next logical step.

Users experiencing the problem can go back to vewere 2.6.2 or adjust DNS settings to use the google free
DNS servers 8.8.8.8 and 8.8.4.4 which should allow them to work around the problem.

Reviewed by Richard.

indra/llmessage/llcurl.cpp

@@ -674,15 +674,7 @@ void LLCurl::Multi::removeEasy(Easy* easy)
 //static
 std::string LLCurl::strerror(CURLcode errorcode)
 {
-#if LL_DARWIN
-	// curl_easy_strerror was added in libcurl 7.12.0.  Unfortunately, the version in the Mac OS X 10.3.9 SDK is 7.10.2...
-	// There's a problem with the custom curl headers in our build that keeps me from #ifdefing this on the libcurl version number
-	// (the correct check would be #if LIBCURL_VERSION_NUM >= 0x070c00).  We'll fix the header problem soon, but for now
-	// just punt and print the numeric error code on the Mac.
-	return llformat("%d", errorcode);
-#else // LL_DARWIN
 	return std::string(curl_easy_strerror(errorcode));
-#endif // LL_DARWIN
 }
 
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