Unbreak alpha: On alpha a long double is the same as a double and

consequently the exponent is only 11 bits. Testing whether the
exponent equals 32767 in that case only effects to compiler warnings
and thus build breakage.

lib/libc/gen/isinf.c

@@ -62,5 +62,9 @@ __isinfl(long double e)
 
 	u.e = e;
 	mask_nbit_l(u);
+#ifndef __alpha__
 	return (u.bits.exp == 32767 && u.bits.manl == 0 && u.bits.manh == 0);
+#else
+	return (u.bits.exp == 2047 && u.bits.manl == 0 && u.bits.manh == 0);
+#endif
 }