HAL_ChibiOS: signal2 does not need to be DMA safe

libraries/AP_HAL_ChibiOS/SoftSigReader.cpp

@@ -34,10 +34,6 @@ bool SoftSigReader::attach_capture_timer(ICUDriver* icu_drv, icuchannel_t chan,
     if (signal == nullptr) {
         return false;
     }
-    signal2 = (uint32_t*)hal.util->malloc_type(sizeof(uint32_t)*SOFTSIG_BOUNCE_BUF_SIZE, AP_HAL::Util::MEM_DMA_SAFE);
-    if (signal2 == nullptr) {
-        return false;
-    }
     _icu_drv = icu_drv;
     //Setup Burst transfer of period and width measurement
     dma = STM32_DMA_STREAM(dma_stream);

libraries/AP_HAL_ChibiOS/SoftSigReader.h

@@ -40,7 +40,7 @@ public:
 
 private:
     uint32_t *signal;
-    uint32_t *signal2;
+    uint32_t signal2[SOFTSIG_BOUNCE_BUF_SIZE];
     static void _irq_handler(void* self, uint32_t flags);
     uint8_t num_timer_channels;
     uint8_t enable_chan_mask;