[sysrst_ctrl,doc] Fix documentation of the flash_wp_l pin

The documentation is incorrect: since the default logic value
of the pin with no override is 0, the only way to release the pin
is to use an override to 1, and NOT to disable the override.

Signed-off-by: Amaury Pouly <[email protected]>

hw/ip/sysrst_ctrl/doc/theory_of_operation.md

@@ -159,9 +159,9 @@ Note that since the `sysrst_ctrl` does not have control over the pad open-drain
 ## Flash Write Protect Output
 
 Upon reset, the `flash_wp_l_o` signal will be asserted active low.
-The software can release `flash_wp_l_o` explicitly by setting [`PIN_OUT_CTL.FLASH_WP_L`](registers.md#pin_out_ctl) to 0 when needed.
 The `flash_wp_l_o` signal does have a corresponding input signal `flash_wp_l_i` - but that one is mainly intended for pad observability and does not have a bypass path to `flash_wp_l_o`.
-Hence, the value of `flash_wp_l_o` defaults to logic 0 when it is not explicitly driven via the override function.
+Hence, the value of `flash_wp_l_o` defaults to asserted low when it is not explicitly driven via the override function.
+The software can release `flash_wp_l_o` explicitly by setting an override to 1, that is setting [`PIN_ALLOWED_CTL.FLASH_WP_L_1`](registers.md#pin_allowed_ctl) to 1, [`PIN_OUT_CTL.FLASH_WP_L`](registers.md#pin_out_ctl) to 1 and [`PIN_OUT_VALUE.FLASH_WP_L`](registers.md#pin_out_value) to 1.
 
 Note that since the `sysrst_ctrl` does not have control over the pad open-drain settings, software should properly initialize the pad attributes of the corresponding pad in the [pinmux configuration](../../pinmux/README.md) before releasing `flash_wp_l_o`.