build: Fix Meson deprecation warnings on the ini file

DEPRECATION: c_args in the [properties] section of the machine file is deprecated, use the [built-in options] section.
DEPRECATION: c_link_args in the [properties] section of the machine file is deprecated, use the [built-in options] section.

card10-cross.ini

@@ -3,11 +3,12 @@ c = 'arm-none-eabi-gcc'
 ar = 'arm-none-eabi-ar'
 strip = 'arm-none-eabi-strip'
 
-[properties]
+[built-in options]
 c_args      = ['-mthumb', '-mcpu=cortex-m4', '-mfloat-abi=softfp', '-mfpu=fpv4-sp-d16', '-Wa,-mimplicit-it=thumb', '-ffunction-sections', '-fdata-sections', '-fsingle-precision-constant', '-fno-isolate-erroneous-paths-dereference']
 
 c_link_args = ['-mthumb', '-mcpu=cortex-m4', '-mfloat-abi=softfp', '-mfpu=fpv4-sp-d16', '-Wl,--start-group', '-lc', '-lnosys', '-Wl,--end-group', '--specs=nano.specs', '-Wl,-wrap,BbBleDrvRand']
 
+[properties]
 target_defs = ['-DTARGET=32665', '-DTARGET_REV=0x4131', '-DBOARD_CARD10=1']
 
 [host_machine]