Don't set SDFAT_FILE_TYPE, default is OK

Fixes #2772

No need to set SDFAT_FILE_TYPE=3 as that is the defaulr value with upstream
SdFat.  Remove it from platform.txt and platform.io build.

platform.txt

@@ -114,7 +114,7 @@ build.espwifitype=
 build.debugscript=picoprobe_cmsis_dap.tcl
 build.picodebugflags=
 build.variantdefines=
-build.sdfatdefines=-DFILE_COPY_CONSTRUCTOR_SELECT=FILE_COPY_CONSTRUCTOR_PUBLIC -DUSE_UTF8_LONG_NAMES=1 -DSDFAT_FILE_TYPE=3 -DDISABLE_FS_H_WARNING=1
+build.sdfatdefines=-DFILE_COPY_CONSTRUCTOR_SELECT=FILE_COPY_CONSTRUCTOR_PUBLIC -DUSE_UTF8_LONG_NAMES=1 -DDISABLE_FS_H_WARNING=1
 
 # Allow Pico boards to be auto-discovered by the IDE
 #discovery.rp2040.pattern={runtime.tools.pqt-python3.path}/python3 -I "{runtime.platform.path}/tools/pluggable_discovery.py"

tools/platformio-build.py

@@ -229,7 +229,6 @@ def is_pio_build():
         # SdFat definitions required for SDFS
         ("FILE_COPY_CONSTRUCTOR_SELECT", "FILE_COPY_CONSTRUCTOR_PUBLIC"),
         ("USE_UTF8_LONG_NAMES", "1"),
-        ("SDFAT_FILE_TYPE", "3"),
         ("DISABLE_FS_H_WARNING", "1")
     ],