sim: erc32: fix build w/out F_{G,S}ETFL

Add conditional logic around fcntl.h F_{G,S}ETFL usage to fix builds
on systems that don't have it (e.g. Windows).  The code is only used
to save & restore limited terminal stdin state.

sim/erc32/ChangeLog

@@ -1,3 +1,9 @@
+2021-06-14  Mike Frysinger  <vapier@gentoo.org>
+
+	* interf.c (sim_open) [F_GETFL]: Only set termsave.
+	(sim_close) [F_SETFL]: Only call fcntl.
+	* sis.c (main) [F_GETFL]: Only set termsave.
+
 2021-06-14  Mike Frysinger  <vapier@gentoo.org>
 
 	* erc32.c [HAVE_TERMIOS_H]: Include termios.h and declare ioc1,

sim/erc32/interf.c

@@ -241,7 +241,9 @@ sim_open (SIM_OPEN_KIND kind, struct host_callback_struct *callback,
     }
 
     sregs.freq = freq ? freq : 15;
+#ifdef F_GETFL
     termsave = fcntl(0, F_GETFL, 0);
+#endif
     INIT_DISASSEMBLE_INFO(dinfo, stdout,(fprintf_ftype)fprintf);
 #ifdef HOST_LITTLE_ENDIAN
     dinfo.endian = BFD_ENDIAN_LITTLE;
@@ -263,9 +265,10 @@ sim_close(SIM_DESC sd, int quitting)
 {
 
     exit_sim();
+#ifdef F_SETFL
     fcntl(0, F_SETFL, termsave);
-
-};
+#endif
+}
 
 SIM_RC
 sim_load(SIM_DESC sd, const char *prog, bfd *abfd, int from_tty)

sim/erc32/sis.c

@@ -219,7 +219,9 @@ main(int argc, char **argv)
     dinfo.endian = BFD_ENDIAN_BIG;
 #endif
 
+#ifdef F_GETFL
     termsave = fcntl(0, F_GETFL, 0);
+#endif
     using_history();
     init_signals();
     ebase.simtime = 0;