[FL-2060] FuriHal: SPI refactoring, flexible bus reconfiguration on fly, same design as i2c. (#853)

* FuriHal: SPI refactoring, flexible bus reconfigration on fly, same desiag as i2c.
* Lib: update CC1101 driver documentation
* FuriHal: update spi symbol names to match naming convention.

firmware/targets/furi-hal-include/furi-hal-sd.h

@@ -5,6 +5,7 @@
 
 #include <stdint.h>
 #include <stdbool.h>
+#include <furi-hal-spi-types.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -24,6 +25,9 @@ void hal_sd_detect_set_low(void);
  */
 bool hal_sd_detect(void);
 
+/** Pointer to currently used SPI Handle */
+extern FuriHalSpiBusHandle* furi_hal_sd_spi_handle;
+
 #ifdef __cplusplus
 }
 #endif