target-i386: Use QEMU instead of Qemu

This new 'QEmu' was recently added.
Replace it by the official all upper case 'QEMU'.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index fdd95be..5521709 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -1303,7 +1303,7 @@
         builtin_x86_defs[i].flags = 1;
 
         /* Look for specific "cpudef" models that */
-        /* have the QEmu version in .model_id */
+        /* have the QEMU version in .model_id */
         for (j = 0; j < ARRAY_SIZE(model_with_versions); j++) {
             if (strcmp(model_with_versions[j], builtin_x86_defs[i].name) == 0) {
                 pstrcpy(builtin_x86_defs[i].model_id, sizeof(builtin_x86_defs[i].model_id), "QEMU Virtual CPU version ");