Define macro BIT() in qca_vendor.h

As qca_vendor.h alone can be included by other applications, define
macro BIT() in qca_vendor.h itself if not yet defined, e.g., by
including utils/common.h before qca_vendor.h.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>

src/common/qca-vendor.h

@@ -19,6 +19,10 @@
 
 #define OUI_QCA 0x001374
 
+#ifndef BIT
+#define BIT(x) (1U << (x))
+#endif
+
 /**
  * enum qca_radiotap_vendor_ids - QCA radiotap vendor namespace IDs
  */