target-i386: Rename struct XMMReg to ZMMReg

The struct represents a 512-bit register, so name it accordingly.

This is just a global search+replace, no other changes are being
introduced.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index 15e325e..372814c 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -732,7 +732,7 @@
     uint64_t _q[8];
     float32 _s[16];
     float64 _d[8];
-} XMMReg; /* really zmm */
+} ZMMReg;
 
 typedef union {
     uint8_t _b[8];
@@ -865,8 +865,8 @@
     float_status mmx_status; /* for 3DNow! float ops */
     float_status sse_status;
     uint32_t mxcsr;
-    XMMReg xmm_regs[CPU_NB_REGS == 8 ? 8 : 32];
-    XMMReg xmm_t0;
+    ZMMReg xmm_regs[CPU_NB_REGS == 8 ? 8 : 32];
+    ZMMReg xmm_t0;
     MMXReg mmx_t0;
 
     uint64_t opmask_regs[NB_OPMASK_REGS];