[lldb] Fix manual CURSES_LIBRARIES tinfo finding

At present, we automatically detect terminfo symbols in CURSES_LIBRARIES
after it is found through `find_package`. However, by introducing a
check for TINFO_LIBRARIES, we break systems which pass all of
CURSES_INCLUDE_DIRS, CURSES_LIBRARIES, and PANEL_LIBRARIES individually
without passing TINFO_LIBRARIES. We'd rather not expose TINFO_LIBRARIES
at all.

This commit preemptively attempts to fix issues encountered
on systems that manually pass CURSES_LIBRARIES which already
contain the necessary terminfo symbols (e.g. 'acs_map').

Additionally, let's not make CURSES_LIBRARIES a list. That was odd
to begin with.

See this breakage in Google Fuchsia:
https://issues.fuchsia.dev/397455029

References Issue #101368

Author: ajordanr-google

lldb/cmake/modules/FindCursesAndPanel.cmake

@@ -6,15 +6,24 @@
 
 include(CMakePushCheckState)
 
-function(lldb_check_curses_tinfo CURSES_LIBRARIES CURSES_HAS_TINFO)
+function(lldb_check_curses_tinfo CURSES_HEADER CURSES_LIBRARIES CURSES_HAS_TINFO)
   cmake_reset_check_state()
   set(CMAKE_REQUIRED_LIBRARIES "${CURSES_LIBRARIES}")
   # acs_map is one of many symbols that are part of tinfo but could
   # be bundled in curses.
-  check_symbol_exists(acs_map "curses.h" CURSES_HAS_TINFO)
+  check_symbol_exists(acs_map "${CURSES_HEADER}" CURSES_HAS_TINFO)
 endfunction()
 
-if(CURSES_INCLUDE_DIRS AND CURSES_LIBRARIES AND TINFO_LIBRARIES AND PANEL_LIBRARIES)
+if(CURSES_INCLUDE_DIRS AND CURSES_LIBRARIES AND PANEL_LIBRARIES)
+  if(NOT HAS_TERMINFO_SYMBOLS)
+    lldb_check_curses_tinfo("${CURSES_INCLUDE_DIRS}/curses.h"
+                            "${CURSES_LIBRARIES}"
+                            CURSES_HAS_TINFO)
+    if (NOT CURSES_HAS_TINFO)
+      message(WARNING "CURSES_LIBRARIES was provided manually but is missing terminfo symbols")
+    endif()
+    mark_as_advanced(CURSES_HAS_TINFO)
+  endif()
   set(CURSESANDPANEL_FOUND TRUE)
 else()
   find_package(Curses QUIET)
@@ -25,7 +34,9 @@ else()
     # Sometimes the curses libraries define their own terminfo symbols,
     # other times they're extern and are defined by a separate terminfo library.
     # Auto-detect which.
-    lldb_check_curses_tinfo("${CURSES_LIBRARIES}" CURSES_HAS_TINFO)
+    lldb_check_curses_tinfo("${CURSES_INCLUDE_DIRS}/curses.h"
+                            "${CURSES_LIBRARIES}"
+                            CURSES_HAS_TINFO)
     if (NOT CURSES_HAS_TINFO)
       message(STATUS "curses library missing terminfo symbols, looking for tinfo separately")
       find_library(TINFO_LIBRARIES NAMES tinfo DOC "The curses tinfo library" QUIET)