fix: strlcpy and strlcat redeclaration on gcc 13.3.0

[luisschwab]

strlcpy and strlcat are being redeclared by strlcpy.h. Removing the import fixes it.

~/git/bitcoin-seeder $ make
g++ -std=c++11 -pthread -O3 -g0 -march=native -Wall -Wno-unused -Wno-sign-compare -Wno-reorder -Wno-comment -c -o netbase.o netbase.cpp
In file included from netbase.cpp:13:
strlcpy.h:27:15: error: ‘size_t strlcpy(char*, const char*, size_t)’ redeclared inline without ‘gnu_inline’ attribute
   27 | inline size_t strlcpy(char *dst, const char *src, size_t siz)
      |               ^~~~~~~
In file included from /usr/include/features.h:502,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/os_defines.h:39,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/c++config.h:679,
                 from /usr/include/c++/13/bits/requires_hosted.h:31,
                 from /usr/include/c++/13/string:38,
                 from netbase.h:7,
                 from netbase.cpp:6:
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:150:1: note: ‘size_t strlcpy(char*, const char*, size_t)’ previously defined here
  150 | __NTH (strlcpy (char *__restrict __dest, const char *__restrict __src,
      | ^~~~~
strlcpy.h:62:15: error: ‘size_t strlcat(char*, const char*, size_t)’ redeclared inline without ‘gnu_inline’ attribute
   62 | inline size_t strlcat(char *dst, const char *src, size_t siz)
      |               ^~~~~~~
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:167:1: note: ‘size_t strlcat(char*, const char*, size_t)’ previously defined here
  167 | __NTH (strlcat (char *__restrict __dest, const char *__restrict __src,
      | ^~~~~
make: *** [Makefile:8: netbase.o] Error 1