adjust partitions for 2MB (#780)

use minimal partitions

Author: blue-2357

boards.txt

@@ -138,7 +138,7 @@ nina_w10.build.variant=nina_w10
 nina_w10.build.board=UBLOX_NINA_W10
 nina_w10.build.f_cpu=240000000L
 nina_w10.build.boot=bootloader
-nina_w10.build.partitions=default
+nina_w10.build.partitions=minimal
 nina_w10.build.flash_mode=dio
 nina_w10.build.flash_size=2MB
 nina_w10.build.flash_freq=40m