meta-ide-support: adjust to provide (e)SDK experience directly in a yocto build

meta-ide-support: adjust to provide (e)SDK experience directly in a yocto build

Specifically:
1. Add a few more toolchain items to DEPENDS so they're available in the recipe sysroot.
2. Use deploy mechanism to place the SDK environment setup file and testdata for testing it
into the image deploy directory.
3. Add ability to run SDK tests via the testsdk class and task. This also requires providing
a testdata json file.
4. Ensure sysroot population always runs, as those items are mean to be picked up
by 'bitbake build-sysroots' into the unified sysroot.

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>