[TOPIC-GPIO] drivers: sensor: isl29035: update to new GPIO API

[pabigot]

Document alert pin behavior, switch to new API.

NOTE: This includes the content of #21434 which should disappear when this is topic-gpio is rebased on master. Only the top commit is relevant to this PR.

[zephyrbot]

All checks passed.

checkpatch (informational only, not a failure)

-:93: WARNING:LONG_LINE: line over 80 characters
#93: FILE: drivers/sensor/isl29035/isl29035_trigger.c:183:
+	gpio_pin_configure(drv_data->gpio, DT_INST_0_ISIL_ISL29035_INT_GPIOS_PIN,

-:94: WARNING:LONG_LINE: line over 80 characters
#94: FILE: drivers/sensor/isl29035/isl29035_trigger.c:184:
+			   GPIO_INPUT | DT_INST_0_ISIL_ISL29035_INT_GPIOS_FLAGS);

- total: 0 errors, 2 warnings, 125 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Your patch has style problems, please review.

NOTE: Ignored message types: AVOID_EXTERNS BRACES CONFIG_EXPERIMENTAL CONST_STRUCT DATE_TIME FILE_PATH_CHANGES MINMAX NETWORKING_BLOCK_COMMENT_STYLE PRINTK_WITHOUT_KERN_LEVEL SPLIT_STRING VOLATILE

NOTE: If any of the errors are false positives, please report
      them to the maintainers.

Tip: The bot edits this comment instead of posting a new one, so you can check the comment's history to see earlier messages.

[dbkinder]

doc changes LGTM.

[carlescufi]

@MaureenHelm can you please review
@pabigot please rebase

[pabigot]

Rebase wasn't needed, but there were some build errors and problems with non-default triggers. Verified and tested again.

[pabigot]

Sanity check failure due to #21568, open for four weeks with no assignee. IMO this should be mergeable.