[Silabs] Move header to common place

[jepenven-silabs]

Unify the class name and move header to common code. Rework of implementation pending.

[github-actions]

PR #26105: Size comparison from cdf3c61 to d2c7482

Increases (1 build for qpg)

platform	target	config	section	cdf3c61	d2c7482	change	% change
qpg	lighting-app	qpg6105+debug	(read/write)	1166624	1166632	8	0.0
			.text	613724	613732	8	0.0

Full report (2 builds for qpg)

platform	target	config	section	cdf3c61	d2c7482	change	% change
qpg	lighting-app	qpg6105+debug	(read/write)	1166624	1166632	8	0.0
			.bss	99308	99308	0	0.0
			.data	856	856	0	0.0
			.text	613724	613732	8	0.0
	lock-app	qpg6105+debug	(read/write)	1136704	1136704	0	0.0
			.bss	94452	94452	0	0.0
			.data	860	860	0	0.0
			.text	583800	583800	0	0.0

[github-actions]

PR #26105: Size comparison from a202465 to 112a3a2

Full report (1 build for cc32xx)

platform	target	config	section	a202465	112a3a2	change	% change
cc32xx	lock	CC3235SF_LAUNCHXL		0	0	0	0.0
			(read only)	643081	643081	0	0.0
			(read/write)	203848	203848	0	0.0
			.ARM.attributes	44	44	0	0.0
			.ARM.exidx	8	8	0	0.0
			.bss	197248	197248	0	0.0
			.comment	194	194	0	0.0
			.data	1480	1480	0	0.0
			.debug_abbrev	933224	933224	0	0.0
			.debug_aranges	87760	87760	0	0.0
			.debug_frame	302028	302028	0	0.0
			.debug_info	20327053	20327053	0	0.0
			.debug_line	2687476	2687476	0	0.0
			.debug_loc	2838789	2838789	0	0.0
			.debug_ranges	288040	288040	0	0.0
			.debug_str	3042053	3042053	0	0.0
			.ramVecs	780	780	0	0.0
			.resetVecs	64	64	0	0.0
			.rodata	104393	104393	0	0.0
			.shstrtab	232	232	0	0.0
			.stab	204	204	0	0.0
			.stabstr	441	441	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	377625	377625	0	0.0
			.symtab	256832	256832	0	0.0
			.text	536568	536568	0	0.0