Documentation: leds: mt6370: Properly wrap hw_pattern chart

The pattern diagram (chart) of /sys/class/leds/<led>/hw_pattern is
wrapped in literal code block. However, the block indentation is
interrupted by Icurr axis label, hence below warnings:

Documentation/leds/leds-mt6370-rgb.rst:39: WARNING: Literal block ends without a blank line; unexpected unindent.
Documentation/leds/leds-mt6370-rgb.rst:41: WARNING: Line block ends without a blank line.
Documentation/leds/leds-mt6370-rgb.rst:46: WARNING: Unexpected indentation.
Documentation/leds/leds-mt6370-rgb.rst:44: WARNING: Inline substitution_reference start-string without end-string.

Fix the chart indentation by adding 4 more spaces so that the axis label
is in the code block.

Link: https://lore.kernel.org/oe-kbuild-all/202303182310.tB1mUzU7-lkp@intel.com/
Fixes: 4ba9df04b7ac66 ("docs: leds: Add MT6370 RGB LED pattern document")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230319074903.13075-3-bagasdotme@gmail.com

Documentation/leds/leds-mt6370-rgb.rst

@@ -36,7 +36,7 @@ Pattern diagram::
           ^
           |           ============
           |          /            \                                /
-Icurr |         /              \                              /
+    Icurr |         /              \                              /
           |        /                \                            /
           |       /                  \                          /   .....repeat
           |      /                    \                        /