Remove context switch in ppe program exception handler

Change-Id: Iaed6207f1838e3a77fde9eeb945fc1fd1c5c0a91
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/40485
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: PPE CI <ppe-ci+hostboot@us.ibm.com>
Reviewed-by: Sachin Gupta <sgupta2m@in.ibm.com>
Reviewed-by: Soma Bhanutej <soma.bhanu@in.ibm.com>
Reviewed-by: Douglas R. Gilbert <dgilbert@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/40486
Reviewed-by: Hostboot Team <hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>

src/import/chips/p9/procedures/ppe/pk/ppe42/ppe42_exceptions.S

@@ -111,12 +111,8 @@ __alignment_exception:
 
         .org __vectors + 0x00E0
 
-        ### Program exceptions are utilized for emulating the system call
-        ### instruction (0x44000002) which is used for doing context
-        ### switches between threads.  They can also be used by the code
-        ### to signal an exception in an error scenario.
 __program_exception:
-        _pk_ctx_push_as_needed  program_exception_handler 
+        _pk_panic   PPE42_ILLEGAL_INSTRUCTION
 
 
         ############################################################
@@ -219,9 +215,6 @@ dec_handler:
         bl      __pk_timer_handler
         b       check_for_ext_interrupt
 
-program_exception_handler:
-        _pk_panic   PPE42_ILLEGAL_INSTRUCTION
-
         .global __pk_next_thread_resume
 __pk_next_thread_resume: