loadtools/scripts: gtm900.config renamed to gen4.config It turns out that a GTM900 variant exists with 8 MiB flash, thus -h gen8 needs to be used for GTM900 modules as the general case, and the old -h gtm900 config is best renamed to -h gen4, although not currently official for any actual target.

	.section	.magic,"ax",%progbits
	.code	32

	.globl	_Magic_words
_Magic_words:
	.word	0
	.word	_entry