Fixes compile error with gcc 11.2

armv7a-libreelec-linux-gnueabihf-g++ -fPIC -march=armv7-a -mtune=cortex-a8 -mabi=aapcs-linux -Wno-psabi -Wa,-mno-warn-deprecated -mfloat-abi=hard -mfpu=neon-vfpv3 -Wall -pipe  -O2 -fomit-frame-pointer -DNDEBUG -D__NEON_OPT -DGIT_VERSION=6440e1cb65 -O3 -fomit-frame-pointer -finline -fno-builtin -D__LIBRETRO__ -DCPU_arm -DARM_ASSEMBLY -DARMV6_ASSEMBLY -DPANDORA -DROM_PATH_PREFIX=\"./\" -DDATA_PREFIX=\"./data/\" -DSAVE_PREFIX=\"./saves/\" -DRASPBERRY -DPICASSO96 -DUSE_ARMNEON -DINLINE="inline"  -fexceptions -fpermissive   -I./src -I./libretro/osdep -I./src/include -I./libretro -I./libretro/libco -I./libretro/core -I./utils -I./deps/zlib -I./libretro/libco -I./libretro/core -I./libretro/include -I./libretro -I.  -c -o libretro/osdep/pandora.o libretro/osdep/pandora.cpp
libretro/osdep/pandora.cpp: In function 'int target_cfgfile_load(uae_prefs*, char*, int, int)':
libretro/osdep/pandora.cpp:361:10: error: ordered comparison of pointer with integer zero ('char*' and 'int')
  361 |   if(ptr > 0)
      |      ~~~~^~~
libretro/osdep/pandora.cpp: In function 'int check_configfile(char*)':
libretro/osdep/pandora.cpp:407:16: error: ordered comparison of pointer with integer zero ('char*' and 'int')
  407 |         if(ptr > 0)
      |            ~~~~^~~