x86emul/fuzz: correct header (symlink) dependencies

A use of $(x86_emulate.h) was introduced (mirroring what the testharness
has) without realizing that no such variable exists here. (Re)name the
variable (to) "private.h", which better expresses what is included which
way.

Note that because of automatic dependencies tracking, unlike in the test
harness no $(x86.h) variable is needed here - we solely need explicit
dependencies for files which need symlinks created.

Fixes: 9ace97ab9b ("x86emul: split off opcode 0f01 handling")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

tools/fuzz/x86_instruction_emulator/Makefile

@@ -35,14 +35,16 @@ OBJS := fuzz-emul.o x86-emulate.o
 OBJS += x86_emulate/0f01.o x86_emulate/0fae.o x86_emulate/0fc7.o
 OBJS += x86_emulate/decode.o x86_emulate/fpu.o
 
+private.h := x86-emulate.h x86_emulate/x86_emulate.h x86_emulate/private.h
+
 x86-emulate.h: x86_emulate/x86_emulate.h
-x86-emulate.o x86-emulate-cov.o: x86-emulate.h x86_emulate/x86_emulate.c x86_emulate/private.h
+x86-emulate.o x86-emulate-cov.o: x86_emulate/x86_emulate.c $(private.h)
 fuzz-emul.o fuzz-emul-cov.o wrappers.o: x86-emulate.h
 
-$(filter x86_emulate/%.o,$(OBJS)): x86_emulate/%.o: x86_emulate/%.c x86_emulate/private.h $(x86_emulate.h)
+$(filter x86_emulate/%.o,$(OBJS)): x86_emulate/%.o: x86_emulate/%.c $(private.h)
 	$(CC) $(CPPFLAGS) $(CFLAGS) $(CFLAGS_$*.o) -c -o $@ $< $(APPEND_CFLAGS)
 
-$(patsubst %.o,%-cov.o,$(filter x86_emulate/%.o,$(OBJS))): x86_emulate/%-cov.o: x86_emulate/%.c x86_emulate/private.h $(x86_emulate.h)
+$(patsubst %.o,%-cov.o,$(filter x86_emulate/%.o,$(OBJS))): x86_emulate/%-cov.o: x86_emulate/%.c $(private.h)
 	$(CC) $(CPPFLAGS) $(CFLAGS) $(CFLAGS_$*.o) $(GCOV_FLAGS) -c -o $@ $< $(APPEND_CFLAGS)
 
 x86-insn-fuzzer.a: $(OBJS) cpuid.o