qtouch: switch PTC to 8Mhz clock from 12 Mhz

8Mhz is recommended by the tooling and can be divided down to the
required 2Mhz with the ADC prescaler

Author: NickeZ

external/asf4-drivers/Config/hpl_gclk_config.h

@@ -387,7 +387,7 @@
 // <i> Indicates whether generic clock 5 configuration is enabled or not
 // <id> enable_gclk_gen_5
 #ifndef CONF_GCLK_GENERATOR_5_CONFIG
-#define CONF_GCLK_GENERATOR_5_CONFIG 0
+#define CONF_GCLK_GENERATOR_5_CONFIG 1
 #endif
 
 // <h> Generic Clock Generator Control
@@ -404,7 +404,7 @@
 // <i> This defines the clock source for generic clock generator 5
 // <id> gclk_gen_5_oscillator
 #ifndef CONF_GCLK_GEN_5_SOURCE
-#define CONF_GCLK_GEN_5_SOURCE GCLK_GENCTRL_SRC_GCLKGEN1
+#define CONF_GCLK_GEN_5_SOURCE GCLK_GENCTRL_SRC_DFLL
 #endif
 
 // <q> Run in Standby
@@ -446,15 +446,15 @@
 // <i> Indicates whether Generic Clock Generator Enable is enabled or not
 // <id> gclk_arch_gen_5_enable
 #ifndef CONF_GCLK_GEN_5_GENEN
-#define CONF_GCLK_GEN_5_GENEN 0
+#define CONF_GCLK_GEN_5_GENEN 1
 #endif
 // </h>
 
 //<h> Generic Clock Generator Division
 //<o> Generic clock generator 5 division <0x0000-0xFFFF>
 // <id> gclk_gen_5_div
 #ifndef CONF_GCLK_GEN_5_DIV
-#define CONF_GCLK_GEN_5_DIV 62
+#define CONF_GCLK_GEN_5_DIV 6
 #endif
 // </h>
 // </e>

external/asf4-drivers/Config/peripheral_clk_config.h

@@ -33,15 +33,15 @@
 
 // <i> Select the clock source for ADC.
 #ifndef CONF_GCLK_ADC0_SRC
-#define CONF_GCLK_ADC0_SRC GCLK_PCHCTRL_GEN_GCLK2_Val
+#define CONF_GCLK_ADC0_SRC GCLK_PCHCTRL_GEN_GCLK5_Val
 #endif
 
 /**
  * \def CONF_GCLK_ADC0_FREQUENCY
  * \brief ADC0's Clock frequency
  */
 #ifndef CONF_GCLK_ADC0_FREQUENCY
-#define CONF_GCLK_ADC0_FREQUENCY 12000000
+#define CONF_GCLK_ADC0_FREQUENCY 8000000
 #endif
 
 /**