[PATCH] tests/tcg/s390x: Allow specifying extra QEMU options on the command line

[Ilya Leoshkevich]

The use case for this is `make check-tcg EXTFLAGS="-accel kvm"`,
which allows validating the system TCG testcases on real hardware.
EXTFLAGS name is borrowed from tests/tcg/xtensa/Makefile.softmmu-target.
While at it, use += instead of = in order to be consistent with the
other architectures.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tests/tcg/s390x/Makefile.softmmu-target | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/tcg/s390x/Makefile.softmmu-target 
b/tests/tcg/s390x/Makefile.softmmu-target
index 1078655dd31..4ca0dac7257 100644
--- a/tests/tcg/s390x/Makefile.softmmu-target
+++ b/tests/tcg/s390x/Makefile.softmmu-target
@@ -1,6 +1,6 @@
 S390X_SRC=$(SRC_PATH)/tests/tcg/s390x
 VPATH+=$(S390X_SRC)
-QEMU_OPTS=-action panic=exit-failure -nographic -kernel
+QEMU_OPTS+=-action panic=exit-failure -nographic $(EXTFLAGS) -kernel
 LINK_SCRIPT=$(S390X_SRC)/softmmu.ld
 CFLAGS+=-ggdb -O0
 LDFLAGS=-nostdlib -static
-- 
2.45.1