staging: rtl8723bs: remove unused global efuse variables

staging: rtl8723bs: remove unused global efuse variables

Remove several global efuse variables from rtw_efuse.c and their
corresponding extern declarations in rtw_efuse.h.

These variables (fakeEfuseBank, BTEfuseUsedBytes, etc.) are completely
unused legacy code. The driver currently maintains the efuse state
properly within the 'efuse_hal' structure, which is encapsulated
inside 'hal_com_data'.

The removal of this dead code cleans up the global namespace and
resolves multiple checkpatch.pl warnings regarding CamelCase naming
conventions. Verified by compilation that no functional code references
these variables.

Signed-off-by: Marcos Andrade <marcosandrade95963@gmail.com>
Reviewed-by: Ethan Tidmore <ethantidmore06@gmail.com>
Link: https://patch.msgid.link/20260316220435.2249-1-marcosandrade95963@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>