doc: include driver subdirectories

The file tree was reorganized but the subdirectories were never added
to the docs.

Author: dlech

lib/pbio/doc/doxygen.conf

@@ -790,10 +790,23 @@ WARN_LOGFILE           =
 # spaces. See also FILE_PATTERNS and EXTENSION_MAPPING
 # Note: If this tag is empty the current directory is searched.
 
-INPUT                  = ../include/pbdrv \
+INPUT                  = \
+                         ../drv \
+                         ../drv/adc \
+                         ../drv/battery \
+                         ../drv/button \
+                         ../drv/clock \
+                         ../drv/counter \
+                         ../drv/gpio \
+                         ../drv/ioport \
+                         ../drv/led \
+                         ../drv/pwm \
+                         ../drv/reset \
+                         ../drv/uart \
+                         ../drv/usb \
+                         ../include/pbdrv \
                          ../include/pbio \
                          ../include/pbsys \
-                         ../drv \
                          ../src \
                          ../sys \