tests/plugin: Remove duplicate insn log from libinsn.so

This is a perfectly natural occurrence for x86 "rep movb",
where the "rep" prefix forms a counted loop of the one insn.

During the tests/tcg/multiarch/memory test, this logging is
triggered over 350000 times.  Within the context of cross-i386-tci
build, which is already slow by nature, the logging is sufficient
to push the test into timeout.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

tests/plugin/insn.c

@@ -19,7 +19,6 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
 #define MAX_CPUS 8 /* lets not go nuts */
 
 typedef struct {
-    uint64_t last_pc;
     uint64_t insn_count;
 } InstructionCount;
 
@@ -51,13 +50,7 @@ static void vcpu_insn_exec_before(unsigned int cpu_index, void *udata)
 {
     unsigned int i = cpu_index % MAX_CPUS;
     InstructionCount *c = &counts[i];
-    uint64_t this_pc = GPOINTER_TO_UINT(udata);
-    if (this_pc == c->last_pc) {
-        g_autofree gchar *out = g_strdup_printf("detected repeat execution @ 0x%"
-                                                PRIx64 "\n", this_pc);
-        qemu_plugin_outs(out);
-    }
-    c->last_pc = this_pc;
+
     c->insn_count++;
 }