Restore old qspi_alt_size_t values as compatibility macros

Author: Kyle Kearney

TESTS/mbed_hal/qspi/qspi_test_utils.h

@@ -102,10 +102,10 @@ struct Qspi {
 #define ADDR_SIZE_24 QSPI_CFG_ADDR_SIZE_24
 #define ADDR_SIZE_32 QSPI_CFG_ADDR_SIZE_32
 
-#define ALT_SIZE_8  8u
-#define ALT_SIZE_16 16u
-#define ALT_SIZE_24 24u
-#define ALT_SIZE_32 32u
+#define ALT_SIZE_8  QSPI_CFG_ALT_SIZE_8
+#define ALT_SIZE_16 QSPI_CFG_ALT_SIZE_16
+#define ALT_SIZE_24 QSPI_CFG_ALT_SIZE_24
+#define ALT_SIZE_32 QSPI_CFG_ALT_SIZE_32
 
 #define STATUS_REG      QSPI_CMD_RDSR
 #define CONFIG_REG0      QSPI_CMD_RDCR0

hal/qspi_api.h

@@ -62,6 +62,13 @@ typedef enum qspi_address_size {
  */
 typedef uint8_t qspi_alt_size_t;
 
+// The following defines are provided for backwards compatibilty. New code should explicitly
+// specify the required number of alt bits.
+#define QSPI_CFG_ALT_SIZE_8 8u
+#define QSPI_CFG_ALT_SIZE_16 16u
+#define QSPI_CFG_ALT_SIZE_24 24u
+#define QSPI_CFG_ALT_SIZE_32 32u
+
 /** QSPI command
  *
  * Defines a frame format. It consists of instruction, address, alternative, dummy count and data