[Patch] Document: Update Dsc spec to all empty value for HIIPcd

["Feng, Bob C" <bob.c.feng@intel.com>]

https://bugzilla.tianocore.org/show_bug.cgi?id=1466

Update Dsc spec to all empty value for HIIPcd.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
---
 2_dsc_overview/29_pcd_sections.md            | 4 ++--
 3_edk_ii_dsc_file_format/310_pcd_sections.md | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/2_dsc_overview/29_pcd_sections.md b/2_dsc_overview/29_pcd_sections.md
index 791125f..d84d2f4 100644
--- a/2_dsc_overview/29_pcd_sections.md
+++ b/2_dsc_overview/29_pcd_sections.md
@@ -230,11 +230,11 @@ example:
 `[PcdsDynamicHii.common.Sku1]`
 
 While the format for content of this section is as follows, note that the
 backslash character is used here to indicate the continuation of the line:
 
-`PcdTokenSpaceGuidCName.PcdCName|VariableName|VariableGuid|VariableOffset[|HiiDefaultValue[|HiiAttrubte]]`
+`PcdTokenSpaceGuidCName.PcdCName|VariableName|VariableGuid|VariableOffset[|[HiiDefaultValue][|HiiAttrubte]]`
 
 For VOID* PCDs, the HiiDefaultValue will be a pointer; specifying the optional
 HiiDefaultValue has no meaning.
 
 The optional HII Attribute entry is a comma separated list of attributes as
@@ -340,11 +340,11 @@ Specifying a `SKUID` for an HII PCD selection is optional, for example:
 `[PcdsDynamicExHii.common.Sku1]`
 
 While the format for content of this section is as follows, note that the
 backslash character is used here to indicate the continuation of the line:
 
-`PcdTokenSpaceGuidCName.PcdCName|VariableName|VariableGuid|VariableOffset[|HiiDefaultValue]`
+`PcdTokenSpaceGuidCName.PcdCName|VariableName|VariableGuid|VariableOffset[|[HiiDefaultValue]]`
 
 The optional HII Attribute entry is a comma separated list of attributes as
 described in Table 9 HII Attributes.
 
 **Note:** The VariableName field in the HII format PCD entry must not be an empty string.
diff --git a/3_edk_ii_dsc_file_format/310_pcd_sections.md b/3_edk_ii_dsc_file_format/310_pcd_sections.md
index f9f1359..f982d60 100644
--- a/3_edk_ii_dsc_file_format/310_pcd_sections.md
+++ b/3_edk_ii_dsc_file_format/310_pcd_sections.md
@@ -503,11 +503,11 @@ sections of the DSC file.
 <VpdMaxSize>     ::= {<IntNum>} {<UINT16>} [<FS> <StringValue>]
 <HiiEntry>       ::= <PcdName> <FS> <HiiString> <Field2> <EOL>
 <HiiString>      ::= {<CArray>} {<UnicodeString>}
 <Field2>         ::= <FS> <VariableGuid> <FS> <VariableOffset> [<ValueField>]
 <VariableGuid>   ::= <CName>
-<ValueField>     ::= <FS> <DefaultValue> [<FS> <HiiAttrs>]
+<ValueField>     ::= <FS> [<DefaultValue>] [<FS> <HiiAttrs>]
 <VariableOffset> ::= <Number>
 <DefaultValue>   ::= if (pcddatumtype == "BOOLEAN"):
                        {<BoolType>} {<Expression>}
                      elif (pcddatumtype == "UINT8"):
                        {<NumValUint8>} {<Expression>}
@@ -721,11 +721,11 @@ sections of the DSC file.
 <VpdMaxSize>     ::= {<LongNum>} {<UINT32>} [<FS> <StringValue>]
 <HiiEntry>       ::= <PcdName> <FS> <HiiString> <Field2> <EOL>
 <HiiString>      ::= {<CArray>} {<UnicodeString>}
 <Field2>         ::= <FS> <VariableGuid> <FS> <VariableOffset> [<ValueField>]
 <VariableGuid>   ::= <CName>
-<ValueField>     ::= <FS> <DefaultValue> [<FS> <HiiAttrs>]
+<ValueField>     ::= <FS> [<DefaultValue>] [<FS> <HiiAttrs>]
 <VariableOffset> ::= <Number>
 <DefaultValue>   ::= if (pcddatumtype == "BOOLEAN"):
                        {<BoolType>} {<Expression>}
                      elif (pcddatumtype == "UINT8"):
                        {<NumValUint8>} {<Expression>}
-- 
2.20.1.windows.1