CMake build structure, target and style fixes #47

	name: CI
	on: [push, pull_request]
	permissions:
	contents: read # to fetch code (actions/checkout)
	jobs:
	debian:
	name: build (Debian)
	runs-on: ubuntu-latest
	container: jforissier/optee_client_ci_debian
	steps:
	- name: Checkout
	uses: actions/checkout@v3
	- name: arm64 with make
	run: make -j O=out-make-aarch64 CROSS_COMPILE=aarch64-linux-gnu-
	- name: armhf with make
	run: make -j O=out-make-armhf CROSS_COMPILE=arm-linux-gnueabihf-
	- name: arm64 with cmake
	run: \|
	set -e -v
	mkdir out-cmake-aarch64 && cd out-cmake-aarch64
	PKG_CONFIG=aarch64-linux-gnu-pkg-config cmake .. -DCMAKE_C_COMPILER=aarch64-linux-gnu-gcc
	make -j
	- name: armhf with cmake
	run: \|
	set -e -v
	mkdir out-cmake-armhf && cd out-cmake-armhf
	PKG_CONFIG=arm-linux-gnueabihf-pkg-config cmake .. -DCMAKE_C_COMPILER=arm-linux-gnueabihf-gcc
	make -j
	ubuntu:
	name: build (Ubuntu)
	runs-on: ubuntu-latest
	container: jforissier/optee_client_ci_ubuntu
	steps:
	- name: Checkout
	uses: actions/checkout@v3
	- name: arm64 with make
	run: make -j O=out-make-aarch64 CROSS_COMPILE=aarch64-linux-gnu-
	- name: armhf with make
	run: make -j O=out-make-armhf CROSS_COMPILE=arm-linux-gnueabihf-
	- name: arm64 with cmake
	run: \|
	set -e -v
	mkdir out-cmake-aarch64 && cd out-cmake-aarch64
	PKG_CONFIG=aarch64-linux-gnu-pkg-config cmake .. -DCMAKE_C_COMPILER=aarch64-linux-gnu-gcc
	make -j
	- name: armhf with cmake
	run: \|
	set -e -v
	mkdir out-cmake-armhf && cd out-cmake-armhf
	PKG_CONFIG=arm-linux-gnueabihf-pkg-config cmake .. -DCMAKE_C_COMPILER=arm-linux-gnueabihf-gcc
	make -j

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