Add explicit fpu in commandline

Works in sync with upcoming arduino-builder for precompiled libraries

Author: facchinm

boards.txt

@@ -19,6 +19,8 @@ nano33ble.build.variant=ARDUINO_NANO33BLE
 nano33ble.build.mcu=cortex-m4
 nano33ble.build.extra_flags=
 nano33ble.build.architecture=cortex-m4
+nano33ble.build.fpu=fpv4-sp-d16
+nano33ble.build.float-abi=softfp
 nano33ble.build.board=ARDUINO_NANO33BLE
 nano33ble.build.ldscript=linker_script.ld
 nano33ble.compiler.mbed.arch.define=-DARDUINO_ARCH_NRF52840

platform.txt

@@ -18,12 +18,12 @@ compiler.warning_flags.all=-Wall -Wextra
 
 compiler.path={build.compiler_path}
 compiler.c.cmd={build.crossprefix}gcc
-compiler.c.flags=-c {compiler.warning_flags} -Os -g -nostdlib "@{compiler.mbed.defines}" "@{compiler.mbed.cflags}" {compiler.mbed.arch.define} -MMD -mcpu={build.mcu}
+compiler.c.flags=-c {compiler.warning_flags} -Os -g -nostdlib "@{compiler.mbed.defines}" "@{compiler.mbed.cflags}" {compiler.mbed.arch.define} -MMD -mcpu={build.mcu} -mfloat-abi={build.float-abi} -mfpu={build.fpu}
 compiler.c.elf.cmd={build.crossprefix}g++
 compiler.c.elf.flags=-Wl,--gc-sections {compiler.warning_flags} -Wl,--as-needed
-compiler.S.flags=-c -g -x assembler-with-cpp -Os -mcpu={build.mcu}
+compiler.S.flags=-c -g -x assembler-with-cpp -Os -mcpu={build.mcu} -mfloat-abi={build.float-abi} -mfpu={build.fpu}
 compiler.cpp.cmd={build.crossprefix}g++
-compiler.cpp.flags=-c {compiler.warning_flags} -g -Os -nostdlib "@{compiler.mbed.defines}" "@{compiler.mbed.cxxflags}" {compiler.mbed.arch.define} -MMD -mcpu={build.mcu}
+compiler.cpp.flags=-c {compiler.warning_flags} -g -Os -nostdlib "@{compiler.mbed.defines}" "@{compiler.mbed.cxxflags}" {compiler.mbed.arch.define} -MMD -mcpu={build.mcu} -mfloat-abi={build.float-abi} -mfpu={build.fpu}
 compiler.ar.cmd={build.crossprefix}ar
 compiler.ar.flags=rcs
 compiler.objcopy.cmd=