Add explicit device logic to the iOS build script

[a-maurice]

Description

Provide details of the change, and generalize the change in the PR title above.

When building for iOS and tvOS device, set the appropriate CMAKE_OSX_SYSROOT value. Seems to be necessary based on Xcode and Cmake versions.

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Testing

Describe how you've tested these changes. Link any manually triggered Integration tests or CPP binary SDK Packaging Github Action workflows, if applicable.

Building locally.

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Type of Change

Place an x the applicable box:

• Bug fix. Add the issue # below if applicable.
• New feature. A non-breaking change which adds functionality.
• Other, such as a build process or documentation change.

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Notes

• Bug fixes and feature changes require an update to the Release Notes section of release_build_files/readme.md.
• Read the contribution guidelines CONTRIBUTING.md.
• Changes to the public API require an internal API review. If you'd like to help us make Firebase APIs better, please propose your change in a feature request so that we can discuss it together.

[gemini-code-assist]

Code Review

This pull request updates the CMake configuration script for iOS and tvOS to set the -DCMAKE_OSX_SYSROOT parameter when the platform variant is 'device'. The reviewer suggested simplifying the nested conditional blocks by using a dictionary mapping for the platform variants to their respective SDK sysroots to improve readability and maintainability.

[gemini-code-assist]

To improve readability and maintainability, we can simplify the nested conditional blocks by using a dictionary mapping for the platform variants to their respective SDK sysroots. This avoids repetitive if/elif checks and makes the configuration logic cleaner and more idiomatic.

Suggested change

	cmd.append('-DCMAKE_SYSTEM_NAME=iOS')
	if platform_variant == 'simulator':
	cmd.append('-DCMAKE_OSX_SYSROOT=iphonesimulator')
	elif platform_variant == 'device':
	cmd.append('-DCMAKE_OSX_SYSROOT=iphoneos')
	elif apple_os == 'tvos':
	cmd.append('-DCMAKE_SYSTEM_NAME=tvOS')
	if platform_variant == 'simulator':
	cmd.append('-DCMAKE_OSX_SYSROOT=appletvsimulator')
	elif platform_variant == 'device':
	cmd.append('-DCMAKE_OSX_SYSROOT=appletvos')
	cmd.append('-DCMAKE_SYSTEM_NAME=iOS')
	sysroot = {'simulator': 'iphonesimulator', 'device': 'iphoneos'}.get(platform_variant)
	if sysroot:
	cmd.append('-DCMAKE_OSX_SYSROOT={0}'.format(sysroot))
	elif apple_os == 'tvos':
	cmd.append('-DCMAKE_SYSTEM_NAME=tvOS')
	sysroot = {'simulator': 'appletvsimulator', 'device': 'appletvos'}.get(platform_variant)
	if sysroot:
	cmd.append('-DCMAKE_OSX_SYSROOT={0}'.format(sysroot))