Update to c/c++ 17

Author: h2zero

platform.txt

@@ -30,13 +30,13 @@ compiler.warning_flags.all=-Wall -Wextra
 
 compiler.path={runtime.tools.gcc-arm-none-eabi-9.3.1-1.path}/bin/
 compiler.c.cmd=arm-none-eabi-gcc
-compiler.c.flags=-mcpu={build.mcu} -mthumb -c -g -Os {compiler.warning_flags} {build.float_flags} -Wno-unused-parameter -Wno-sign-compare -Wno-old-style-declaration -std=gnu11 -ffunction-sections -fdata-sections -nostdlib --param max-inline-insns-single=500 -MMD
+compiler.c.flags=-mcpu={build.mcu} -mthumb -c -g -Os {compiler.warning_flags} {build.float_flags} -Wno-unused-parameter -Wno-sign-compare -Wno-old-style-declaration -std=gnu17 -ffunction-sections -fdata-sections -nostdlib --param max-inline-insns-single=500 -MMD
 compiler.c.elf.cmd=arm-none-eabi-g++
 compiler.c.elf.flags=-Os -Wl,--gc-sections -save-temps
 compiler.S.cmd=arm-none-eabi-gcc
 compiler.S.flags=-c -g -x assembler-with-cpp
 compiler.cpp.cmd=arm-none-eabi-g++
-compiler.cpp.flags=-mcpu={build.mcu} -mthumb -c -g -Os {compiler.warning_flags} {build.float_flags} -Wno-unused-parameter -std=gnu++11 -ffunction-sections -fdata-sections -fno-threadsafe-statics -nostdlib --param max-inline-insns-single=500 -fno-rtti -fno-exceptions -MMD
+compiler.cpp.flags=-mcpu={build.mcu} -mthumb -c -g -Os {compiler.warning_flags} {build.float_flags} -Wno-unused-parameter -std=gnu++17 -ffunction-sections -fdata-sections -fno-threadsafe-statics -nostdlib --param max-inline-insns-single=500 -fno-rtti -fno-exceptions -MMD
 compiler.ar.cmd=arm-none-eabi-ar
 compiler.ar.flags=rcs
 compiler.objcopy.cmd=arm-none-eabi-objcopy