s390x: add bits/hwcap.h

aligned with linux arch/s390/include/asm/elf.h
(these macros should be exported into uapi, but they are not)

arch/s390x/bits/hwcap.h

@@ -0,0 +1,15 @@
+#define HWCAP_S390_ESAN3	1
+#define HWCAP_S390_ZARCH	2
+#define HWCAP_S390_STFLE	4
+#define HWCAP_S390_MSA		8
+#define HWCAP_S390_LDISP	16
+#define HWCAP_S390_EIMM		32
+#define HWCAP_S390_DFP		64
+#define HWCAP_S390_HPAGE	128
+#define HWCAP_S390_ETF3EH	256
+#define HWCAP_S390_HIGH_GPRS	512
+#define HWCAP_S390_TE		1024
+#define HWCAP_S390_VXRS		2048
+#define HWCAP_S390_VXRS_BCD	4096
+#define HWCAP_S390_VXRS_EXT	8192
+#define HWCAP_S390_GS		16384