tests: Use EXIT_AM_SKIP instead of 77 directly

tests/esxutilstest.c

@@ -280,9 +280,9 @@ VIRT_TEST_MAIN(mymain)
 
 #else
 
-int main (void)
+int main(void)
 {
-    return 77; /* means 'test skipped' for automake */
+    return EXIT_AM_SKIP;
 }
 
 #endif /* WITH_ESX */

tests/qemuhelptest.c

@@ -485,6 +485,9 @@ VIRT_TEST_MAIN(mymain)
 
 #else
 
-int main (void) { return (77); /* means 'test skipped' for automake */ }
+int main(void)
+{
+    return EXIT_AM_SKIP;
+}
 
 #endif /* WITH_QEMU */

tests/qemuxml2argvtest.c

@@ -548,6 +548,9 @@ VIRT_TEST_MAIN(mymain)
 
 #else
 
-int main (void) { return (77); /* means 'test skipped' for automake */ }
+int main(void)
+{
+    return EXIT_AM_SKIP;
+}
 
 #endif /* WITH_QEMU */

tests/vmx2xmltest.c

@@ -283,9 +283,9 @@ VIRT_TEST_MAIN(mymain)
 
 #else
 
-int main (void)
+int main(void)
 {
-    return 77; /* means 'test skipped' for automake */
+    return EXIT_AM_SKIP;
 }
 
 #endif /* WITH_VMX */

tests/xml2vmxtest.c

@@ -294,9 +294,9 @@ VIRT_TEST_MAIN(mymain)
 
 #else
 
-int main (void)
+int main(void)
 {
-    return 77; /* means 'test skipped' for automake */
+    return EXIT_AM_SKIP;
 }
 
 #endif /* WITH_VMX */