[DISCO_F429ZI] added a description why there are commented pwm config lines

Some text to explain the commented pwm pin config. Remove some Timer5
based pwm config.

The Timer5 lines are not allowed as pwm configs because the timer is
used by the us_ticker as mentioned at the start of the block. I've
overseen to remove these lines.

Author: ohagendorf

libraries/mbed/targets/hal/TARGET_STM/TARGET_DISCO_F429ZI/pwmout_api.c

@@ -37,6 +37,17 @@
 
 // TIM5 cannot be used because already used by the us_ticker
 static const PinMap PinMap_PWM[] = {
+    /*
+     * The lines below show all combinations to conect a port pin with a timer. Commented
+     * lines are alternative possibilities not used per default. But they can be changed
+     * manually instead of the suggested configuration. For example you can see that on 
+     * PA_5 you can have a PWM using either Timer2/Channel1 or Timer8/Channel1N. Today I 
+     * have decided to use Timer2/Channel1. But you can also notice that Timer2/Channel1 
+     * is also used on PA_0. That means that today you cannot output two different PWM 
+     * signals on PA_0 and PA_5 at the same time. If someone wants this, he will need to 
+     * change the timer that is used on PA_5. This is why the other possibilities are
+     * commented to make this change easier without looking deeply into the mcu datasheet.
+     */
     {PA_0,  PWM_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2)}, // TIM2_CH1
     {PA_1,  PWM_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2)}, // TIM2_CH2
     {PA_2,  PWM_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2)}, // TIM2_CH3
@@ -103,14 +114,10 @@ static const PinMap PinMap_PWM[] = {
     {PE_13, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM1)},  // TIM1_CH3
     {PE_14, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM1)},  // TIM1_CH4
 
-    {PH_10, PWM_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM5)},  // TIM5_CH1
-    {PH_11, PWM_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM5)},  // TIM5_CH2
-    {PH_12, PWM_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM5)},  // TIM5_CH3
     {PH_13, PWM_8, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8)},  // TIM8_CH1N
     {PH_14, PWM_8, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8)},  // TIM8_CH2N
     {PH_15, PWM_8, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8)},  // TIM8_CH3N
 
-    {PI_0,  PWM_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM5)},  // TIM5_CH4
     {PI_2,  PWM_8, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8)},  // TIM8_CH4
     {PI_5,  PWM_8, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8)},  // TIM8_CH1
     {PI_6,  PWM_8, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8)},  // TIM8_CH2