onlyvalidsamples does not work as expected in SARDeburst

Description

In SARDeburst, the boolean parameter onlyvalidsamples does not work as expected because its value is retrived by using IsParameterEnabled("onlyvalidsamples"). Therefore the mode extracting valid pixels is selected if the parameter is set (to true or false) and disabled if the parameter is not set (as expected as the default value of the parameter is false). This is not how boolean parameters are supposed to work!

In addition, the start_sample and end_sample fields are not written correclty in the keywordist (and in output geom files) in the mode with all samples, the integer values are left uninitialized:

support_data.geom.bursts.burst[0].azimuth_anx_time:  2214.6792991092
support_data.geom.bursts.burst[0].azimuth_start_time:  2021-03-09T06:07:58.711867
support_data.geom.bursts.burst[0].azimuth_stop_time:  2021-03-09T06:08:23.795859
support_data.geom.bursts.burst[0].end_line:  12203
support_data.geom.bursts.burst[0].end_sample:  4178860053
support_data.geom.bursts.burst[0].start_line:  0
support_data.geom.bursts.burst[0].start_sample:  2962116592
support_data.geom.bursts.number:  1
support_data.geom.bursts.number_lines_per_burst:  1508
support_data.geom.bursts.number_samples_per_burst:  23150

start_sample and end_sample are not used in this mode so this bug does not affect the results.

Steps to reproduce

With a slc product:

The following command

bin/otbcli_SARDeburst  -in ~/datas/S1Data/S1B_IW_SLC__1SDV_20210309T060756_20210309T060823_025934_0317E8_900A.SAFE/measurement/s1b-iw1-slc-vv-20210309t060758-20210309t060823-025934-0317e8-004.tiff  -out ~/datas/test/out.tif

keeps all samples from the input product whereas the following

bin/otbcli_SARDeburst  -in ~/datas/S1Data/S1B_IW_SLC__1SDV_20210309T060756_20210309T060823_025934_0317E8_900A.SAFE/measurement/s1b-iw1-slc-vv-20210309t060758-20210309t060823-025934-0317e8-004.tiff  -out ~/datas/test/out.tif -onlyvalidsamples false
bin/otbcli_SARDeburst  -in ~/datas/S1Data/S1B_IW_SLC__1SDV_20210309T060756_20210309T060823_025934_0317E8_900A.SAFE/measurement/s1b-iw1-slc-vv-20210309t060758-20210309t060823-025934-0317e8-004.tiff  -out ~/datas/test/out.tif -onlyvalidsamples true

keeps only the valid samples.

Configuration information

OTB 7.4 and develop