build/mingw: style fixup after tonobitc merge.

Use `#defined(...)` instead of `#defined ...`.

Remove comments about issues - anyone removing those lines can check blame
to see why they were added.

Add tonobitc to AUTHORS.md.

AUTHORS.md

@@ -25,6 +25,7 @@ updated by many others.
 * Benjamin Herrenschmidt <ozbenh>
 * Joe4782
 * gacheson
+* tonobitc
 
 ...and many others. See:
 

compat.h

@@ -47,7 +47,7 @@ static inline int nanosleep(const struct timespec *req, struct timespec *rem)
 }
 #endif
 
-#if defined __MINGW32__ && !defined __MINGW64_VERSION_MAJOR
+#if defined(__MINGW32__) && !defined(__MINGW64_VERSION_MAJOR)
 // Reported unneded in https://github.com/veox/sgminer/issues/37 */
 static inline int sleep(unsigned int secs)
 {

sgminer.c

@@ -35,7 +35,7 @@
 #ifndef WIN32
 #include <sys/resource.h>
 #else
-#include <winsock2.h> //before windows.h to resolve ws2tcpip.h conflict https://github.com/veox/sgminer/issues/12
+#include <winsock2.h>
 #include <windows.h>
 #endif
 #include <ccan/opt/opt.h>
@@ -3044,7 +3044,7 @@ static void kill_mining(void)
 		if (thr && PTH(thr) != 0L)
 			pth = &thr->pth;
 		thr_info_cancel(thr);
-#if !defined WIN32 || defined __MINGW64_VERSION_MAJOR
+#if !defined(WIN32) || defined(__MINGW64_VERSION_MAJOR)
 		if (pth && *pth)
 			pthread_join(*pth, NULL);
 #else