doc, v850: Clean up V850 options and documentation [PR122243]

doc, v850: Clean up V850 options and documentation [PR122243]

gcc/ChangeLog
	PR other/122243
	* config/v850/v850.opt: Copy-edit documentation strings.
	(mdebug): Make Undocumented.
	(mno-strict-align): Add RejectNegative.
	(mUS-bit-set): Make Undocumented.
	* doc/invoke.texi (Option Summary) <V850 Options>: Remove
	redundant -mno- forms from list.  Add missing entries.
	(V850 Options): Add @opindex for negative forms.  Combine
	entries for -mapp-regs and -mno-app-regs.  Document -msmall-sld,
	-mno-strict-align, and -mjump-tables-in-data-section.