[lldb] Remove summary for signed char *

It conflicts with the summary for BOOL * (aka signed char *). This
partially reverts D112709.

lldb/source/DataFormatters/FormatManager.cpp

@@ -730,7 +730,7 @@ void FormatManager::LoadSystemFormatters() {
       GetCategory(m_system_category_name);
 
   sys_category_sp->GetRegexTypeSummariesContainer()->Add(
-      RegularExpression(R"(^((un)?signed )?char ?(\*|\[\])$)"), string_format);
+      RegularExpression(R"(^(unsigned )?char ?(\*|\[\])$)"), string_format);
 
   sys_category_sp->GetRegexTypeSummariesContainer()->Add(
       std::move(any_size_char_arr), string_array_format);

lldb/test/API/functionalities/data-formatter/stringprinter/main.cpp

@@ -62,7 +62,7 @@ int main (int argc, char const *argv[])
     //%
     //% for c in ["", "const"]:
     //%   for v in ["", "volatile"]:
-    //%     for s in ["", "signed", "unsigned"]:
+    //%     for s in ["", "unsigned"]:
     //%       summary = '"'+c+v+s+'char"'
     //%       self.expect_var_path(c+v+s+"chararray", summary=summary)
     //% # These should be printed normally

lldb/test/API/lang/c/flexible-array-members/TestCFlexibleArrayMembers.py

@@ -18,7 +18,7 @@ class TestCase(TestBase):
                 lldb.SBFileSpec("main.c"))
 
         self.expect_var_path("c->flexible", type="char[]", summary='"contents"')
-        self.expect_var_path("sc->flexible", type="signed char[]", summary='"contents"')
+        # self.expect_var_path("sc->flexible", type="signed char[]", summary='"contents"')
         self.expect_var_path("uc->flexible", type="unsigned char[]", summary='"contents"')
         # TODO: Make this work
         self.expect("expr c->flexible", error=True,