Claude review: video: leds: backlight: lm3533: Support getting LED sources from DT

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

This patch has multiple bugs:

**Bug — wrong register in LED driver**: The second `lm3533_update` for LVLED4/5 writes to `LM3533_REG_OUTPUT_CONF1` instead of `LM3533_REG_OUTPUT_CONF2`:
```c
/* LVLED4 and LVLED5 */
ret = lm3533_update(led->lm3533, LM3533_REG_OUTPUT_CONF1,  // should be OUTPUT_CONF2
                    output_cfg_val >> OUTPUT_CONF2_SHIFT,
                    OUTPUT_CONF2_MASK);
```

**Bug — off-by-one in led-sources reading**: Both drivers have the same issue:
```c
if (led->num_leds > 0 && led->num_leds < LM3533_MAX_LEDS) {
```
This excludes the case where `num_leds == LM3533_MAX_LEDS` (5), meaning if all 5 LVLEDs are specified, the array is never read. The condition should be `<=`:
```c
if (led->num_leds > 0 && led->num_leds <= LM3533_MAX_LEDS) {
```
Same issue in the backlight driver with `LM3533_MAX_LED_STRINGS` (2) — specifying both HVLED strings skips the read.

**Design flaw — wide masks clobber other banks**: The output config registers are shared between all banks. The LED driver uses `OUTPUT_CONF1_MASK = GENMASK(7, 2)` which covers ALL three LVLEDs, and `OUTPUT_CONF2_MASK = GENMASK(3, 0)` covers both LVLED4/5. Each LED bank probe overwrites the entire set of LVLED mappings, clobbering configurations from previously-probed banks.

Compare with the existing `lm3533_set_lvled_config()` which correctly computes a **per-LVLED** 2-bit mask:
```c
mask = LM3533_LED_ID_MASK << shift;
val = led << shift;
ret = lm3533_update(lm3533, reg, val, mask);
```

The patch should use narrow per-LVLED masks or, better yet, call the existing `lm3533_set_lvled_config`/`lm3533_set_hvled_config` functions instead of reimplementing the register manipulation.

**Same clobbering issue in backlight**: The backlight driver uses `OUTPUT_CONF1_MASK = GENMASK(1, 0)`, writing both HVLED config bits at once. If bank A probes first and sets HVLED1, bank B probing second will overwrite both bits.

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Generated by Claude Code Patch Reviewer