apply alvinhochun's gbagame patches
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add system in EMUFILE_FILE to switch correctly between read/write modes; add system in EMUFILE_FILE to (optionally) track current file position and avoid redundant fseeks - this code is UNTESTED.
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add better console feedback when gbagame .sav is being scanned, to make developers less likely to think the emulator is frozen

git-svn-id: https://svn.code.sf.net/p/desmume/code/trunk@5041 5577840e-afb3-4e59-9ef3-2b7f898b1952
Fix file seeking of gba ROM and fix seeking behaviour of EMUFILE_FILE

git-svn-id: https://svn.code.sf.net/p/desmume/code/trunk@5042 5577840e-afb3-4e59-9ef3-2b7f898b1952