Merge changes from topic "sgi_to_nrd" into integration
* changes:
refactor(sgi): replace references to "SGI"/"sgi" for neoverse_rd
refactor(sgi): rename "CSS_SGI"" macro prefixes to "NRD"
refactor(sgi): move apis and types to "nrd" prefix
refactor(sgi): replace build-option prefix to "NRD"
refactor(sgi): move neoverse_rd out of css
refactor(sgi): move from "sgi" to "neoverse_rd"
feat(sgi): remove unused SGI_PLAT build-option
fix(sgi): align to misra rule for braces
feat(rde1edge): remove support for RD-E1-Edge
fix(rdn2): populate TOS_CONFIG only when SPMC_AT_EL3 is enabled
fix(board): update spi_id max for sgi multichip platforms