Doxygen comment typo (#1463)

diff --git a/src/rp2_common/hardware_gpio/include/hardware/gpio.h b/src/rp2_common/hardware_gpio/include/hardware/gpio.h
index 95acc11..b6ccb87 100644
--- a/src/rp2_common/hardware_gpio/include/hardware/gpio.h
+++ b/src/rp2_common/hardware_gpio/include/hardware/gpio.h
@@ -344,7 +344,7 @@
  */
 void gpio_set_drive_strength(uint gpio, enum gpio_drive_strength drive);
 
-/*! \brief Determine current slew rate for a specified GPIO
+/*! \brief Determine current drive strength for a specified GPIO
  *  \ingroup hardware_gpio
  *
  * \sa gpio_set_drive_strength