pmb.flasher: Remove use of args

I can't test this because of:

ERROR: unable to select packages:
  libstdc++-14.2.0-r4:
    breaks: g++-armv7-14.2.0-r3[libstdc++=14.2.0-r3]
    satisfies: g++-14.2.0-r4[libstdc++=14.2.0-r4]
               libstdc++-dev-14.2.0-r4[libstdc++=14.2.0-r4]
               gcc-14.2.0-r4[so:libstdc++.so.6]
               gcc-armv7-14.2.0-r3[so:libstdc++.so.6]
               binutils-2.43.1-r1[so:libstdc++.so.6]
               ccache-4.10.2-r0[so:libstdc++.so.6]
               lzip-1.24.1-r1[so:libstdc++.so.6]

But this should be ready for review now.

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To test, attempt to flash a device using the pmbootstrap flasher subcommand. Anything goes.