add curlver.h include to umbrella header to ensure version checks work

[toffaletti]

attempting to fix #5157

I believe the issue is that the version checks here are failing:

swift-corelibs-foundation/Sources/_CFURLSessionInterface/include/CFURLSessionInterface.h

Lines 39 to 43 in c466923

	#if LIBCURL_VERSION_MAJOR > 7 || (LIBCURL_VERSION_MAJOR == 7 && LIBCURL_VERSION_MINOR > 84) || (LIBCURL_VERSION_MAJOR == 7 && LIBCURL_VERSION_MINOR == 84 && LIBCURL_VERSION_PATCH >= 0)
	#define NS_CURL_CURLINFO_CAINFO_SUPPORTED 1
	#else
	#define NS_CURL_CURLINFO_CAINFO_SUPPORTED 0
	#endif

because LIBCURL_VERSION_MAJOR etc have not been defined.
because <curl/curlver.h> hasn't been included anywhere yet.
It is included here, but after CFURLSessionInterface.h has already been processed.

swift-corelibs-foundation/Sources/_CFURLSessionInterface/CFURLSessionInterface.c

Lines 22 to 24 in c466923

	#include "CFURLSessionInterface.h"
	#include "CFString.h"
	#include <curl/curl.h>

swift-corelibs-foundation/Sources/_CFURLSessionInterface/include/static-module.map

Line 2 in c466923

umbrella header "CFURLSessionInterface.h"

[parkera]

Let us know if this works for you.

[toffaletti]

Let us know if this works for you.

I might need your help in understanding how to test this. I haven't built a static sdk from scratch.