peeling data with unflagged NaNs results in NaNs

[d3v-null]

hyperdrive di-cal automatically flags 80kHz edges and the dc bin, resulting in NaNs in the solution.

Birli blindly applies these solutions, and if edge channels are not flagged, then this results in unflagged NaNs in the data. MWATelescope/Birli#190

hyperdrive di-cal --data 1271683982_*gpubox*.fits 1271683982.metafits --uvw-min 75l --uvw-max 1667l --source-list /data/curtin_mwaeor/GGSM_updated.fits --num-sources 8000 --outputs hyp_soln_1271683982.bin
birli --avg-time-res 4 --avg-freq-res 40 --apply-di-cal hyp_soln_1271683982.bin -M birli_1271676902_cal1271683982_4s_40kHz.ms -m 1271676902.metafits -- 1271676902_2*.fits
hyperdrive peel -v -d birli_1271676902_cal1271683982_4s_40kHz.ms 1271676902.metafits --ms-data-column-name DATA -s birli_1271676902_cal1271683982_4s_40kHz_peel_per_source.ao.txt -o birli_1271676902_cal1271683982_4s_40kHz_peeled.ms --outputs birli_1271676902_cal1271683982_4s_40kHz_peel_offsets.json --iono-sub 100

[peel_gpu] t  4 pass 10 s     0|GLEAM_J090225_051639 @ ra +135.61 d   -5.28 | a      NaN b      NaN g NaN | da      NaN db      NaN dg NaN |
[peel_gpu] t  4 pass 10 s     1|GLEAM_J085328_034104 @ ra +133.37 d   -3.68 | a      NaN b      NaN g NaN | da      NaN db      NaN dg NaN |
[peel_gpu] t  4 pass 10 s     2|GLEAM_J093631+042207 @ ra +144.13 d   +4.37 | a      NaN b      NaN g NaN | da      NaN db      NaN dg NaN |                                                         
[peel_gpu] t  4 pass 10 s     3|GLEAM_J085711_033940 @ ra +134.30 d   -3.66 | a      NaN b      NaN g NaN | da      NaN db      NaN dg NaN |

hyperdrive should treat NaNs as flagged data