add TH5-512 hwsku into gcu support list (#3898)

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#### What I did
add TH5-512 hwsku into gcu support list

#### How I did it

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#### Previous command output (if the output of a command-line utility has changed)

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Author: mssonicbld

generic_config_updater/gcu_field_operation_validators.conf.json

@@ -30,7 +30,8 @@
                 "th2": [ "Arista-7260CX3-D108C10", "Arista-7260CX3-D108C8",  "Arista-7260CX3-C64", "Arista-7260CX3-Q64" ],
                 "th3": [ "Nokia-IXR7220-H3" ],
                 "th4": [ "Nokia-IXR7220-H4-64D", "Nokia-IXR7220-H4-32D" ],
-                "th5": [ "Nokia-IXR7220-H5-64D", "Arista-7060X6-64DE", "Arista-7060X6-64PE", "Arista-7060X6-64PE-C224O8", "Arista-7060X6-64PE-C256S2", "Nokia-IXR7220-H5-64O", "Nokia-IXR7220-H5-32D"],
+                "th5": [ "Nokia-IXR7220-H5-64D", "Arista-7060X6-64DE", "Arista-7060X6-64PE", "Arista-7060X6-64PE-C224O8", "Arista-7060X6-64PE-C256S2", "Nokia-IXR7220-H5-64O", "Nokia-IXR7220-H5-32D",
+                         "Arista-7060X6-64PE-B-C512S2", "Arista-7060X6-64PE-B-C448O16", "Arista-7060X6-64PE-B-O128"],
                 "td2": [ "Force10-S6000", "Force10-S6000-Q24S32", "Arista-7050-QX32", "Arista-7050-QX-32S", "Nexus-3164", "Arista-7050QX32S-Q32" ],
                 "td3": [ "Arista-7050CX3-32S-C32", "Arista-7050CX3-32S-D48C8", "Arista-7050CX3-32S-C28S4" ],
                 "td4": [ "Nokia-IXR7220-D4-36D" ],