tests/tcg: drop test-i386-fprem from TESTS when not SLOW

This is a very slow running test which we only enable explicitly.
However having it in the TESTS lists would confuse additional tests
like the plugins test which want to run on all currently enabled
tests.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

tests/tcg/i386/Makefile.target

@@ -7,10 +7,8 @@ VPATH 		+= $(I386_SRC)
 
 I386_SRCS=$(notdir $(wildcard $(I386_SRC)/*.c))
 ALL_X86_TESTS=$(I386_SRCS:.c=)
-I386_TESTS:=$(filter-out test-i386-ssse3, $(ALL_X86_TESTS))
+SKIP_I386_TESTS=test-i386-ssse3
 X86_64_TESTS:=$(filter test-i386-ssse3, $(ALL_X86_TESTS))
-# Update TESTS
-TESTS=$(MULTIARCH_TESTS) $(I386_TESTS)
 
 #
 # hello-i386 is a barebones app
@@ -36,9 +34,12 @@ run-test-i386-fprem: test-i386-fprem test-i386-fprem.ref
 	$(call run-test,test-i386-fprem, $(QEMU) $<,"$< on $(TARGET_NAME)")
 	$(call diff-out,test-i386-fprem, test-i386-fprem.ref)
 else
-run-test-i386-fprem: test-i386-fprem
-	$(call skip-test, $<, "SLOW")
+SKIP_I386_TESTS+=test-i386-fprem
 endif
 
+# Update TESTS
+I386_TESTS:=$(filter-out $(SKIP_I386_TESTS), $(ALL_X86_TESTS))
+TESTS=$(MULTIARCH_TESTS) $(I386_TESTS)
+
 # On i386 and x86_64 Linux only supports 4k pages (large pages are a different hack)
 EXTRA_RUNS+=run-test-mmap-4096