pixhawk 固件Firmware内执行make px4fmu-v2_default 编译报错解决办法

/bin/sh: 1: Tools/check_cmake.sh: Permission denied
Makefile:44: Not a valid CMake version or CMake not installed.
Makefile:45: On Ubuntu, install or upgrade via:
Makefile:46: 
Makefile:47: 3rd party PPA:
Makefile:48: sudo add-apt-repository ppa:george-edison55/cmake-3.x -y
Makefile:49: sudo apt-get update
Makefile:50: sudo apt-get install cmake
Makefile:51: 
Makefile:52: Official website:
Makefile:53: wget https://cmake.org/files/v3.4/cmake-3.4.3-Linux-x86_64.sh
Makefile:54: chmod +x cmake-3.4.3-Linux-x86_64.sh
Makefile:55: sudo mkdir /opt/cmake-3.4.3
Makefile:56: sudo ./cmake-3.4.3-Linux-x86_64.sh --prefix=/opt/cmake-3.4.3 --exclude-subdir
Makefile:57: export PATH=/opt/cmake-3.4.3/bin:$PATH
Makefile:58: 
Makefile:59: *** Fatal.  Stop.

mkdir -p ~/src
cd ~/src
git clone https://github.com/PX4/Firmware.git
cd Firmware
git submodule update --init --recursive
cd ..