After Xcode finishes beta, check OS support

[stephen-hawley]

I was seeing an issue with Xcode 13b4 when the minimum version of the OS was set to anything less than 12.0 so I set the minimum version to 12.0 and removed the 32 bit targets since those were preventing a clean build.

This was happening with either a direct or indirect reference to Network and this is likely due to the Network source code.

When Xcode is out of beta, revisit this.
In the swiftglue Makefile change the settings for debug and release iOS to:

		--device-archs arm64 armv7 armv7s --simulator-archs i386 x86_64 \
		--module-name XamGlue --minimum-os-version 10.2 \

Also in SwiftRuntimeLibrary/Makefile change back to

XAMGLUE_IOS = $(TOP)/swiftglue/bin/$(configuration)/iphone/FinalProduct/XamGlue.xcframework/ios-i386_x86_64-simulator/XamGlue.framework