spec/build/cpukit/optsmp.yml: Update list of SMP BSPs

The list formerly included the erc32 and pc386 varants which do not
support multi-core. Added the pc386 variants which include the
support necessary for multi-core.

spec/build/cpukit/optsmp.yml

@@ -23,9 +23,7 @@ enabled-by:
 - bsps/aarch64/xilinx-zynqmp
 - bsps/arm/xilinx-zynq
 - bsps/powerpc/qoriq
-- i386/pc386
-- i386/pc486
-- i386/pc586
+- i386/pc586sse
 - i386/pc686
 - riscv/beaglevfire
 - riscv/griscv
@@ -48,7 +46,6 @@ enabled-by:
 - riscv/rv64imafdc_medany
 - riscv/rv64imafd_medany
 - riscv/kendrytek210
-- sparc/erc32
 - sparc/gr712rc
 - sparc/gr740
 - sparc/leon3