There is no regular_breakpoint_inserted_here_p definition at all, so
this patch removes the declaration.
gdb:
2017-10-26  Yao Qi  <yao.qi@linaro.org>
	* breakpoint.h (regular_breakpoint_inserted_here_p): Remove.
+2017-10-26  Yao Qi  <yao.qi@linaro.org>
+
+       * breakpoint.h (regular_breakpoint_inserted_here_p): Remove.
+
 2017-10-26  Yao Qi  <yao.qi@linaro.org>
 
        * break-catch-sig.c (signal_catchpoint_breakpoint_hit): Make
 
 extern int breakpoint_inserted_here_p (const address_space *,
                                       CORE_ADDR);
 
-extern int regular_breakpoint_inserted_here_p (struct address_space *, 
-                                              CORE_ADDR);
-
 extern int software_breakpoint_inserted_here_p (const address_space *,
                                                CORE_ADDR);